FS RS soe ae ae oa arm ay Fae ep «wire nae See u eM es 4c 7% 4 si meet ae a m2 ' 1 aha a . ‘ ‘ i . , —- tr. i 7 7 : Fit + - ees aes A Meir: a ) —# — or teas FIRTH-STERLING STAINLESS STEEL FIRTH-STERLING STEEL COMPANY Genera I ce and Works: McKeesport, Pa. Boston Hartford Philadelphia Cleveland Cetroit Los Angeles San Francisco Price $1.00 Net # oe tts . PM es . 4 » abe in ? i y s & "2 ‘2 me -~* e é a [en rd, 2 oe La Copyright, 1923. by FIRTH-STERLING STEEL COMPANY McKEESPORT, PA. F re ing » . ~ ez APs, . +> a . 7 Wo » ef a a => ee 8 ¢ “= ee es 7 as - , ; A 1 x As y “ L 7 ‘Th’ invention all admir’d, and each, how he To be th’ inventor miss’d; so easy it seem’d, Once found, which yet unfound most would have thought Impossible.” JoHN MILTON [B. 1608] Table of Contents iecetace - - - History - - - Applications - - Types of Stainless Steel - Heat ‘Treatment and Working Chemical Analysis - - Physical: Properties - - Resistance to Various Agencies of Baist, otain and «Corrosion Terms of Warranty 2 Index - - - ARs yes HIS book has been prepared with the object of | bringing before those interested in Stainless Steel such data as may save the trouble and ex- pense of conducting experiments in the fields where experience has shown that it has, or has not, been found suitable. ‘The information is based upon experiments made in our laboratory; in the laboratory of the Firths in Shefheld, England; and upon reports from custom- ers who are using the material. Special acknowledgment is due Messrs. Thos. Firth & Sons, Ltd., of Shefheld, our own Metallurgical Staff, at McKeesport, Pa., and the many customers who have cooperated. Although Stainless Steel is now used for a great variety of purposes new applications are being found from day to day; consequently any treatise on it at this time is of a preliminary nature. Later editions must necessarily follow. Firth-Sterling Steel Company faly vat, 1923. HISTORY Sy aiiracee STEEL has marked an epoch in the manufacture of steel secondary only in impor- tance to High Speed Steel at the beginning of the present century. Although its development was some- what retarded during the late War, its worth has now been fully proven under actual service conditions and it has established itself as a valuable commercial product. The value of high percentages of Chromium in im- parting special properties to 1ron and steel has been known for many years. As early as 1872 the effect of Chromium in producing non-corrosive properties in steel was vaguely described by two Englishmen who made an application for a patent which was never granted. There were no important developments until about 1912 when Mr. Harry Brearley, in the laboratory of Thos. Firth & Sons, Ltd., Shefheld, England, dis- covered the combination of alloys, and developed the necessary manufacturing details, to produce a steel which would neither rust, stain nor tarnish when sub- ject to the ordinary agencies of rust, stain and corrosion. At the time that Mr. Harry Brearley was develop- ing Stainless Steel in England, Mr. Elwood Haynes was working independently in the United States on the same problem. Both were granted United States pat- ents. These and other patents have since been acquired by the American Stainless Steel Company. (The [9] 1O FIR PE =o UE RINGS TEE aC Ovi Paine American Stainless Steel Company owns the Stainless Steel Patents, but does not manufacture or sell steel.) FIRTH-STERLING STAINLESS STEEL and FIRTH-STERLING STAINLESS IRON are manufactured under a license from this company. The work by Thos. Firth & Sons, Ltd., Sheffield, England, and the Firth-Sterling Steel Company, McKeesport, Pa., during the years since 1912, has brought the steel to its present state of perfection. Dur- ing the War its use was restricted to war purposes, many tons of it going into valves for aeroplane motors. Since the War its development has been vigorously carried on, and engineers have recognized its value in many directions. At about the same time that Stainless Steel was discovered in the Shefheld Works, another type of stainless material, “Stainless Iron,” was made in the laboratory of the Firth-Sterling Steel Company at McKeesport. Its development was also delayed by the War. el Ab LIN: Tel oan a pela kabel; I] Applications and Possibilities There is a wide field for rustless, stainless steel or iron because, since the earliest use of steel and iron, rust and corrosion have been their greatest enemies. ‘These are being overcome. Cutlery was first to take any consider- able tonnage of Stainless Steel, but Stainless Steel and Stainless Iron have been used with success for a variety of purposes including: Aeroplane Parts Air Compressor Valves Automobile Parts and Fittings Artificial Limb Fittings baances, nite, Edges, Beams, etc. | Ball Bearings Bicycle Parts Bits, etc. (Horses) Bolts, Nuts, etc. Bottling Machinery Bread-making Machinery Buckles: shoe, Harness, etc. Builders’ Tools Butchers’ Rails, Hooks, CLC: Carburetor Needles, Jets, Screws, etc. Clock Parts Cold Storage Equipment Cooking Utensils Cutlery Dairy Apparatus Dental Instruments Dies Drawing Instruments Electrical Appliances Enemess Acro, Gas, Oil, CrG. Fishing Tackle Forks Gauges Golf Club Heads Gun Parts js PCD Rel Po 2 Rae, G3 eta eG ev een eae House Fittings | Railroad Equipment Instruments, Musical Refrigerator Parts Keys Roller Bearings ni vcst Saddlery Hardware Laboratory Fittings Scale aah Locks Sewing Machine Parts Machinery Parts Soap - manufacturing Micrometer Frames Machinery Motion Picture Machinery Soda Fountain Parts Motor Cycle Parts Surgical Instruments Moulds Tools Needles Turbine Blading, Ornamental Metal’ Work Nozzles, ete. Paper and Pulp Machinery Washing Machine Parts Parts Water Meter Parts Periscope Parts Weighing Machine Parts Phonograph Parts Yacht Fittings Pump Rods and Parts CoPEASIEN UL EeSiseueay ek 13 Types of Firth-Sterling Stainless Steel Stainless Steel is supplied in three types, viz: 1 Steel Annealed Zs Steel Particularly Annealed Be Tron STEEL ANNEALED is a-material requir- ing heat treatment, and proper finishing, to bring out its rustless and stainless qualities. “he same heat treat- ment has the effect of producing maximum strength. The tensile strength of pieclmied petreatcds is approximately 110 tons—See Physical Properties, page 27. STEEL PARTICULARLY ANNEALED: As stated above this steel in the regularly annealed condi- tion requires heat treatment to make it stainless but we have a method of giving the steel what we call a “Par- ticular Annealing” which produces machinable steel that is stainless without further heat treatment. It is necessary, however, to remove the surface of the par- ticularly annealed steel the same as the regularly an- nealed steel but this operation is considerably more difficult. The harder the steel, the more stainless it is; there- fore, our aim is to make the Particularly Annealed Steel just as hard as possible and still have it ma- chinable. I4 FIRTH -STERLEN GS TB eCO MPA Ney IRON has the general characteristics of wrought iron in that it is soft in the manufactured state and requires no annealing. Its physical proper- ties and stainlessness can be improved by heat treating, but it remains machinable. It is exceedingly ductile and can be cold worked like a mild steel. The tensile strength of Iron is thirty to forty tons which may be increased somewhat by heating to about 1900° F. and air cooling or quenching in oil. In the natural state Iron machines about the same as ordinary bar iron. Iron shows good stainless properties in the forged condition, but the oxidized surface must be removed. CAUTION! Any trace of oxide in Stainless Steel Annealed Stainless Steel Particularly Annealed Stainless Iron causes a seat for electrolytic action which invariably results in corrosion. This 1s a matter of vital impor- tance. SRATN LESS Sisk L Is Firth-Sterling Stainless Steel Heat Treatment Forging * Steel is more difficult to forge than regular boorestec!. In this respect it resembles High Speed Steel. Steel does not absorb heat readily, hence it is necessary to soak it at a low temperature, in the meiveou isu) EF. for a-long. period of time, as a preliminary measure to insure softness and uniform Beawme for forging. In general it should be left in the furnace two to three times as long as ordinary steels of the same size and shape. Between the tem- Perrturcssot 1700° F. and 2000° F., Dteclecan be forged without danger of rupture, but below 1700° F., it forges with difficulty and if forcibly deformed at this temperature by heavy blows, excessive strains and breakage will result. Frequent reheating is, there- fore, recommended. Steel is an air-hardening steel and if al- lowed to cool in the air from its forging heat becomes hard. Just how hard the steel will be, depends upon the temperature to which it has been previously heated and also upon the cross-section of the finished product. The hardness may vary to a considerable extent. For * For forging Iron see Page 19. 16 FIRTH+STERUING- SLE EL COM Paes instance, it may correspond to a Brinell. number as high as 550 if the initial heating temperature was be- tween 1/00° F. and 2000° F. If an excessively high forging temperature is used, such as one in excess of 2200° F., the steel is burned and the resultant forged mass is soft, but brittle, and shows a Brinell in the vicinity of 300. No general use therefore should be made of the resultant hardness of air-cooled forgings. Attempts to hammer knife blades and thin sections until they are black, with the object of making them hard and resilient, should be discouraged; results ob- tained are not only very unreliable as regards uniform hardness, but the material is in a highly stressed condi- tion and liable to break. Forgings made in this manner will rust or corrode. Normalizing and Annealing The critical point of Steel is in the vicinity of 1530° F. As with ‘any other air-hardening steels, normalizing is impossible. ‘The range of hardening — and that of normalizing are almost identical, hence the failure of the process. Strains incidental to forg- ing and machining can be relieved by holding the steel at a temperature of about 1300° F. for a short time, and then allowing it to cool in the air. To anneal Steel to get the best machining properties, it should be held for some time at a tem- perature of from 1350° F. to 1400° F. and allowed to cool either in the furnace or in the open air. BLA UNL Bos S LEE LU I i get Hardening The proper hardening range for Steel is from 1750° F. to 1900° F., depending upon size and hard- ness desired. ‘The steel being an air-hardening one, thin sections or intricate shapes which are likely to warp or break if quenched, can be hardened by air cooling from the higher temperatures of the range, but the work will not be quite so hard as if it had been cooled in oil or water. ‘The steel shows its max- imum hardness when quenched in water or brine, but for all general purposes, quenching in oil at 1800° F. to 1850° F. will give the best results. The higher the quenching temperature, within reasonable limits, the better the general results will be. Although Steel hardens at a comparatively high tem- perature, its hardening heat must not be confused with figiecnegrohn speed Steel. Considerable care should be exercised in heating Steel for hardening as it absorbs heat very slowly. In heating for hardening it should be held in the furnace about two to three times as long as ordinary steels to reach a uniform temperature. Wherever practicable, Steel should be given a thorough preheating at a temperature of about 1300°F. before being placed in the full hardening heat. This is especially applicable to heavy sections. 1S BERTH-STERTEN Gos PEER ICOUlE eae Tempering The strains set up in hardening should be relieved by drawing the temper. The extent to which the steel is drawn is limited by the purpose intended. For in- stance where a piece drawn to 575° F.—950° F. will show a tensile strength of approximately 100 tons and a Brinell hardness exceeding 500, increasing the drawing temperature to 1350° F. reduces the tensile strength to approximately 50 tons and the Brinell hardness to approximately 300. The effect of various heats is illustrated on pages 29, 30, 33 and 34. The heating curves illustrated in the charts on pages 33 and 34 were taken from the Bureau of Standards Scientific Paper No. 426, pages 512 and 513. Firth= Sterling Stainless Steel was used in these tests. Discoloration at High Temperatures: The colors which appear on polished steel as it is heated are frequently called “temper colors” and are due to very thin films of oxidized metal. Firth-Sterling Stainless Steel resists oxidation and more heat is re- quired to produce a given color than in ordinary tool steels, as is illustrated by the table on the opposite page. STAINLESS STEEL © 10 Temper Colors APPEARS ON APPEARS ON COLOR TOOL STEEL STAINLESS STEEL Deg. C. Deg. F. Deot. Ce Derek. [Sue OS see eS 220) 428 250 +82 eile iat a ee 230 446 300 Bie ache oitaw— brownish ..... 240 464 350 662 Hemienisn= piutple «... 0... 260 500 400 ipo Reddish—purple brown..... 270 518 450 842 ll) Gy t 290 554 500 932 feepiet bive—yviolet........ 300 Due 550 1022 id UG Sn 310 590 600 BhL2 rem IWe «o.oo =... 620 608 650 1202 Coe) (nd 96 340 644 700 1292 PevemisheGstay 4. .......-- 360 680 750 1382 The above colors are only approximate and vary in different lights and because of surface conditions, also by reason of the conditions under which the heat- ing has been done. Forging Iron In forging Iron, as in forging Steel, Paeee-sential, that the Iron be allowed to soak at a low temperature for some time to insure uniform heating. It is also important that the maximum forg- ing heat be kept below 1900° F. At higher tempera- tures the Iron tends to stiffen or harden slightly and is less machinable. To soften from this condition cool slowly from a temperature of approximately 1400° F. 20) PLR HSS BE RIDIN G5 Tela se Cie oe Welding Steel and Iron can be successfully welded by the electrical contact or fusion method. Both of these processes permit of its union to soft steel. It must be understood, however, that in electric welding, the temperature at the point of contact is raised very high and as a result the metal will be hard, with a tendency toward brittleness. Where possible, welded work should be annealed before further fabri- cation or treatment. ‘The acetylene torch has very little effect upon this steel. It cuts it only with the greatest difficulty. It apparently cannot be satisfactorily welded with the ordinary methods in. a smith’s forge. Brazing and Soldering Steel and Iron can be soldered but, due to certain difficulties presented, the process of brazing is preferred. It is possible to successfully braze the steel 1f proper précautionseatre fakemeneers composition of brazing material, kind of flux, and the temperature of the work. A brass brazing alloy, com- posed of equal parts of copper and zinc is recom- mended. The working temperature is considerably above that customary for such work, being in the vicinity of 1600° F., which is well above the melting point of the brazing alloy. A paste which has given successful results is made by mixing four parts by weight of borax to one of ferric-chloride in hydrochloric acid. ‘This solution D a NSE Sib} Sa Ere mel is used to form a thin paste with zinc-chloride. It is essential that the surface to be brazed be free from dirt, scale and grease. Case Hardening Sass) Steel and LS-tess] Iron cannot be case hard- ened without losing their rustless and stainless char- acteristics. Cold Working Steel and Iron can both be cold rolled and cold drawn. In drawing the steel, however, frequent annealings are necessary and the operation is difficult. Iron can be drawn more readily. The cold working or distortion of the surface of Steel reduces its resistance to rust and corro- sion so that a heat treatment and grinding, or machin- ing becomes necessary. Every trace of scale or oxide must be removed from Steel. Iron after cold working requires no heat treatment to make it resistant to ordinary rusting con- ditions; however, its properties, including machina- bility, mechanical strength, resistance to erosion and corrosion can be improved by suitable heat treatment. Every trace of scale or oxide must be removed from Tron. 22 FUR TI AS Sea Oo ECA MP Aaa Machining Properties In the regularly annealed condition Steel is readily machinable but for some purposes where very sharp angles or unusually smooth machined surfaces are required the Particularly Annealed Steel is recom- mended. Particularly Annealed Steel, however, is difficult to machine. Iron may be machined like ordinary wrought iron or soft steel. Grinding Aside from proper hardening by far the most import- ant process which influences stain-reststance 1s that of grinding. It should be realized at the start that Steel is more difhcult to grind than ordinary steel. As has been mentioned Steel conducts heat very slowly, hence great care should be used in grinding the hardened steel so that heat checks and “grinders. scorch” are not producediiie: Gy armeis. scorch” is a yellowish-brown discoloration, due to im- proper grinding. Frictional heat is generated in local patches on the surface of the work and the resulting dis- coloration has every appearance of stain. This appar- ent stain is in reality a temper color but actual staining is quite likely to occur on surfaces where it is present. Wet grinding is always preferred. The grinding must be deep and thorough. Every trace of forging scale and surface oxidation must be removed. Any STAINLESS STEEL 23 remaining oxides or pits serve as seats for corrosion and an electrolytic action is set up*which rapidly pelequsmover) the surface of the material. A “high polish can be obtained by dry finishing. In the past it has been the belief of some that the surface stability of Steel was due entirely to the degree to which the surface had been polished. On the contrary, the stain and rust-resisting proper- ties are inherent in the steel, being the result of com- position combined with heat treatment. A smooth, highly polished surface is to be desired in order that no pits shall offer “seats of corrosion” or spots where electrolytic action may start. Etching Steel shows a remarkable resistance to the effect of nitric acid whether cold or boiling and in any degree of concentration. It is readily attacked by both hydrochloric and sulphuric but neither of these acids alone serve as a good etching medium. The follow- ing mixtures and solutions have been found to give satisfactory results: 1. Saturated solution of ferric-chloride in hydrochlo- Piewacide to) which a little nitric has been added. Use full strength. 2. For light etching. A saturated solution of copper- sulphate in hydrochloric acid. oA RUR TAA ER EN Ge Seer eC Oise “3. For light-etching. Pivedrechioric acids aes 100 parts Wid teak a vie ee eee 100. parts NercurouspNitratcee =e 7 parts Heat to effect complete solution but use cold, 4. Aqua-Regia. (3 HC] + HNOs))) Thea ate these two acids should be allowed to stand for 24 hours before using. It is used full strength for rapid work but requires very careful handling. In general, the best results are secured where weaker solutions are used and a longer time allowed for etch- - ing. Although in the manufacture of Stainless Steel it is the practice to strike a stencil mark into the red hot bar to indicate the type of steel, and although some foreign cutlery makers stamp the blades instead of etching them, experience has shown that unless all of the black scale, which is driven into the steel by stamping, 1s removed, corrosion may occur in the impression and spread to the polished part of a knife blade or other articles. We recommend etching as always preferable to hot stamping. Methods of Elec- tric Etching are now being worked out. Pickling | Stainless Steel is readily attacked by both Hydrochlo- ric and Sulphuric Acids. A solution of either of these acids will be found suitable for a pickling medium, although the most satisfactory results will be obtained STAINLESS STEEL 7s by the use of a 50% solution of Hydrochloric to which a little Nitric Acid has been added. A boiling solu- tion of 20% Sulphuric Acid has been found to give fairly good results but extra precaution is necessary to prevent pitting. Chemical Analysis ‘The various patents owned by the American Stainless Steel Company, from whom the Firth-Sterling Steel Company obtained its license to manufacture Stainless Steel, contain information on the subject of Chemical Analysis. A typical analysis of Steel shows Carbon .30 and Chrome 13.00. Iron analyzes about the same as Steel excepting that the carbon runs about one-half that of thes otcel. | Firth-Sterling Stainless Steel, like all Firth- Sterling Brands, is sold on Brand and Performance, and not to Carbon Content or Chemical Analysis. GS hE Ele *C.O av ae — a ad < cH op) | an (ae faxta By STAINLESS STEEL 27 Physical Properties Corrosion Although Steel is a steel of high tensile value and one which offers great resistance to heat oxidation and the softening effects which usually accompany high temperatures, its most remarkable property is its surface stability or its resistance to stain, corrosion and rust. ‘The steel shows this exceptional property to a maximum degree when in a properly hardened con- dition and when a clean, smooth surface is exposed. Tensile Properties Steel ranks high among steels noted for their high tensile strength, being a close competitor of the well known Chrome-Nickel and Chrome-Vanadium combinations. It is especially valuable on account of the wide drawing temperature range at which a 200,000 lb. per sq. in. breaking strength can be ob- tained. When properly hardened, little difference is noted in the tensile strength of the steel whether it is drawn at 500° F. or 950° F. When drawn below 500° F. lower values as regards reduction of area and elongation are obtained, while no advantage in tensile strength can be noted. Hardened Steel drawn at 950° F. is non-staining but cannot be machined. ———_——<—__—_ 28 EERE H-s TERLIN.G SS TEEE "COM Page Below is given a table showing some of the physical properties when the steel is drawn at temperatures under 950° F. 200,000. LB. TENSILE STRENGTH CONDIaGs Oil Quenched at 1825° F. Drawn at 575° —950° F. Vieldwnointt see eee 170,000 — 210,000 Ibs. per sq. in. cleensilanotren: le. sete ee oe 200,000 — 250,000 Ibs. per sq. in. Hlongationgeee cts eet ere: 8.0% — 4.0% Kedticttonm cigs. renmwe ese 20.0% — 10.0% Brine.ige ten Oren cae 400 — 475 Scleroscope =o as Sew 60 — 70 When drawn at temperatures in excess of 1050° F., a marked change in tensile properties takcam piace and much lower results are obtained. At still higher temperatures, 1200° F. to 1400° F., the drop takes place very rapidly and the steel becomes exceptionally tough. It might be well to mention at this time that there is an intermediate state which exists between the 225,000 Ibs. and the 150,000 lbs. tensile strength con- dition, over which there is considerable controversy and which offers a wide field for extensive research work. ‘This is illustrated on pages 29 and 30. Dre Ne Ia eS Geno Laks Ls Tensile Properties of Stainless Steel rou). Cy 00) Gr Oil quenched at 1800° FF. Drawn as indicated. DRAWN Ware: ‘EAN Gy SLR ELONG. R.A. BNE FRACTURE AT EBS.SQ.IN. LBS.SQ.IN. %IN-2" ~ % NO. S50 EF. ©2203,508 TaN ag AS 8.3 19.5 480 Flat TOO0SE -195,508 ROO WATE 6.6 15.9 460 Flat 1050° F. 191,450 225,085 7.4 Zo 425 Flat POO ae) 170,558 197,183 LOR Syd 319 Starry io et, 2 145-136 174,864 9.9 lao Sa Starry Poe §131.6/0 159,284 sPibeyl 37.9 535 Starry 1250°0R) ~125;364 150,682 122 39.2 325 Starry Ieee 2 b215155 146,798 12.4 40.5 ele Starry Pesoeahe. ©113°/62 140,857 13.4 43.5 305 Starry 1400° F. 103,900 130,975 14.4 45.8 285 Starry 1450° F. 104,038 137,863 Was: 39.5 305 Cupped 1500° F. 114,138 159,975 12.4 34.0 340 Starry Ann’d 65,000 99,950 270 Shey! MS Starry The mechanical properties of the steel may be modi- fied by raising or lowering the quenching heat. The lower heats give better mechanical properties but at some sacrifice to Hardness and Stain Resistance. One of the standard treatments is illustrated in the follow- ing graphic record. ELONGATION AND REDUCTION OF AREA—PER CENT 30 FURTA-S-FERUUNG* SDE 0 MEP ae 8S 270 80 260 75 250 NCHEG AT IBSS"F- 70 = 240 500 65 § 230 475 60 < 220 450 Qo o Dona el0 425 a (2) 50 zZ 200 400 a : \ 45 z 190 375 a 3 40 X 180 350 t F Sm liz0 325 re FE Ww 30 |, 160 300 a : | z 25 - 150 ae eae 275 sai aes | EN. if 5 130 : BAA { 120 a ail 200 ae ar : Bark 4 5 0 — 175 0 Salo : BS 150 0° ~=—-:100 200 360 400 00 600 700 600 300 00 1100 1200 1300 1400 00 TEMPERATURES DEGREES F. The foregoing graphic chart was drawn from actual figures obtained under test conditions, with the exception of the tensile strength from O° to 400° F, drawing temperatures. BRINNELL NUMBERS S DAENIL So. 5S LEE Ral Scaling at High Temperatures As the temperature of ordinary steel rises the surface oxidizes into a scale of measurable thickness, and even aaderowerca heat the thickness of the scale increases with time. Steel behaves quite differently. i patora temperature of about 1480° FP. the gloss sur- face, due to polishing and hot tinting, 1s permanent and the specimen neither gains nor loses appreciably in weight. Its comparative value in this respect is illustrated by the following chart, which records the percentage loss in weight of various steels after expo- sure for many hours at temperatures above red heat. 40 5 coe ccccscccceesedecsoucccaddssesecsosssoccusss SCALING TESTS Specimens heated at temperature se stated & weighed every 24 hours After removing scale 35 S — Stainless Steel. HS__ High Speed HN Nickel Chrome. N — 25% Nickel. VN 5% A — 3% Carbon Steel. EE a BgSnEs suaessanessasnssasagsnsgassees esaees 30 SGscsseescqceccsen) 20 ite ia! 28 sractttin aii PERCENTAGE LOSS OF WEIGHT eee BEE ths 2Seeesi 72 9 | 120 7 hours ple A6 hours__,|, 46 hours __,i23 hours 1300°F,A335°F, 11380°F,/1480’F.' 1480 sae eaey, i aa : 1560 F. Time and Temperature CHART ON SCALING TESTS 22 FIRTH=S TER DENG TS Ei iC Oo Ea Properties at H. igh ‘Temperatures Steel retains its strength with increasing temperatures to a remarkable extent, being exceeded in this important property only by High Speed Steel, which is considerably more brittle at the elevated temperatures. ‘his property makes the material espe- cially valuable for poppet valves for internal combus- tion engines. For instance, a hardened piece “pulled” at a temperature of 930° F. will show a tensile strength of approximately [00 tons; at [100° F. approximately 35 tons and at 1300° F. approximately 15 tons, with a corresponding increase in elongation. Coefficient of Expansion The degree of expansibility of Steel is of con- siderable importance when used in connection with internal combustion engine valves, steam fittings, etc. Although only slightly less in degree of expansion than ordinary steel, there is sufficient difference to be of considerable advantage. ‘The coefficient of expan- sion of several of the most common materials as com- pared to Steel is given below. These figures represent the linear expansion in fractions of an inch, per degree centigrade, at temperatures up to 200° C. MATERIAL COEFFICIENT OF EXPANSION Steely 2). ae ene eee 0000109 Mild: Steele; (95 ee ee 0000125 Coppet..%. 2626. ee 0000172 Brass 0... 43a eee 0000187 EXPANSION IN MILLIONTHS PER UNIT LENGTH W W STAINLESS ~ STEEL Coefficient of Linear Expansion The following charts are taken from the Bureau of Standards Scientific Paper No. 426, pages 512 and 513. Firth-Sterling Steel was used in these tests. 12000 ‘ aan 8000 4000 TEMPERATURE THERMAL EXPANSION OF ANNEALED STAINLESS STEEL ah 4040 EXPANSION IN MILLIONTHS PER UNIT LENGTH FIRE =STERLUNG 3s PEE ESC ONGr Aaa Coefficient of Linear Expanston—(Continued) ) 300° 600° 900° 52° 572° 11125 1652° TEMPERATURE THERMAL EXPANSION OF HARDENED STAINLESS STEEL Cent. Fehr. Cn OT ASIGN EE ESS eS c1e Ek Bot 4 Modulus of Elasticity Experiments have shown that the modulus of elastic- ity of Steel is slightly in excess of 30,000,000 Ibs. per sq. in. Thermal Conductivity The rate of heat transmission has been determined on Steel in both the hard and soft condition. In the hardened state, the conductivity is less than in the annealed condition, being only about three-fourths of the latter. The thermal conductivity of pure iron is .146 c.g.s. units. By comparison with pure iron, [S=tess] Steel in the soft condition has a thermal conductivity of .0445 c.g.s. units, being about one-third that of iron. Summarized, these figures show the following: Soft Bice Me erie. 0445 c.g.s. units Hard Sue ie, gal Geers 0334 c.g.s. units 1038 NRO oy .1460 c.g.s. units 36 FIRTH -S.TERLING S23 E bi sc 0 MIP he Electrical Conductivity and Resistivity The electrical specific resistance of Steel in the soft condition is fifty to fifty-five microhms per centimeter. In the hardened and tempered condition its resistance is increased to sixty-five to seventy mi- crohms per centimeter. For transmission purposes, it may be compared to pure iron which has a resistance of only one-sixth that of Steel. The resistance of copper is one-seventh that of pure iron, so by com- parison the resistance of the steel is about forty-two times as great as that of copper. For wire to be used in heating units the resistance of the steel is only about half that of Nichrome. A comparative table of the approximate electrical re- sistance of three common substances follows: MATERIAL MICROHMS PER CM. Copper: 2.2 Pure-lron -.3.% 0.00. 4 = ee Steel .....25° 2... eee 50 Nichrome. ......44455 4:0 eee 100 M agnetic Properties Fairly good magnets can be made from Steel. It is a splendid material for use where resistance to corrosion is required. In the soft state, it has the same degree of permeability as that of .90% carbon CoA ONG ES San Sila Bl oe steel in the normalized condition. Its best magnetic properties are brought out when it 1s hardened. ‘Tests on samples of Steel, oil quenched at a tempera- imescumiy 5) gave a coercive force of fifty-eight with a remanence of seventy-two hundred. Aside from its stain-resisting advantages, Steel does not compare favorably with the Firth-Sterling “C” Magnet and Firth-Sterling Special Magnet Steels. Specific Gravity The specific gravity of Dice lmmicme oe DCIILe: considerably less than that of Blue Chip High Speed Steel. A comparison between it, Blue Chip High Speed and Firth-Sterling Special Tool Steels, is as follows: STEEL SPECIFIC GRAVITY Pie@enimerich Speed Steel......... 8.50 fiaeotening, Special’ Pool Steel... 733 Firth-Sterling SiCe arent Reena 7s Melting Point The melting point of Steel is higher than that of High Speed Steel. From observations taken dur- ing the melting of the steel and the pouring and solidi- fication of it into ingots, the melting point has been found to be in the vicinity of 2750° F. FIRTH=-STERUIN GG STEEL COMPA New 38 SME bab eck IPI DIE. 39 Cutting Properties No claim is made for Steel as a suitable steel for metal cutting tools. Its cutting field is limited to table cutlery, pocket knives, hunting knives, surgical instruments, meat cutting blades, leather knives, etc. For these purposes it serves admirably. Occasionally, knives made of Steel are found which are not hard enough for table use. For years makers of cutlery have been accustomed to the working of steel which hardens at a red heat, about 1400° F. A heat approxi- mating a lemon color, (about 1825° F.) is necessary to properly harden pfeclus Ltrcane readily be seen that the tendency is towards quenching at too low a heat and in our experience we have found this to be true. In exceptional cases, however, we have noted that the other extreme is sometimes reached. Knives have been examined which were soft yet brittle on the tip or point of the blade. These blades had no doubt been considerably overheated and burned. Many other factors, such as decarbonization of the cutting edge, improper grinding, and lack of uniform heating and quenching, have in the past given faulty results which have been wrongly attributed to the lack of hardening properties in the steel. Ordinary steel knives stain and discolor readily, which necessitates frequent scouring or cleaning with an abrasive. This daily operation has a tendency to 40 FIRTH-STERLING STEEL COMPANY keep the cutting edge sharp. Steel knives are never scoured, but should be sharpened occasionally by means of a steel or sharpening machine to insure a keen cutting edge. SWE NILES Ses DEE 4] Resistance to Various Agencies of Rust, Stain and Corrosion (when properly treated and finished) Weathering This is the most common of all corrosive influences, but has little or no effect upon Steel and Iron. Samples have been exposed to all types of weather, wet and dry, frost and snow, for many months and at the end of that time have been per- fectly bright and unaffected in any way. Specimens placed in streams have retained their original bright- ness after months of exposure. Water containing a high percentage of dissolved oxygen has no appre- ciable effect upon Steel or Iron. The atmo- sphere of industrial cities has a superficial effect, but this is due essentially to the products of combustion present in such localities. Oxides of sulphur are found in smoke and in the finely divided cinders which are precipitated from it. In connection with a moist atmosphere, such conditions offer quite severe tests to the stain resistance of Steeleand Iron: Sea Water When free from defects, the material is little affected by sea-water. ‘The sea-water or brine solution test, however, is an excellent one for testing the perfection or degree of resistance. FIRTH-STERGIN Gy STEEDS COM a 42 CT Atl NU: EStseee Sele EL 43 Metal Corrosion Where two dissimilar metals are placed in contact in an electrolyte, a galvanic action is set up. This con- © dition is very favorable to corrosion. Steel is no exception to this rule. When it is used in a solu- tion in connection with bearing metals, such as copper, bronze and brass, considerable tarnishing and pitting of the surface is noted. Fruits, Vegetables, Meats and Vinegar There is no doubt but that Steel has made its reputation in the cutlery field. It is in this appli- Ga@eaneeonc ot practical service, that it has clearly demonstrated its superiority over any other material heretofore offered. Millions of Steel knives in use today have permanently established its value for this purpose. Fruit and vegetable acids, such as are present in the orange, lemon, apple, tomato, etc., show no effect whatever. Pickling. vinegar offers a slight attack, due to the presence of hydrochloric acid formed during the reaction of the acetic acid upon the sodium chloride or salt usually found in pickling solutions. Steel and Iron offer complete re- sistance to the effects of lye or ammonia. ‘Thus it can readily be seen that their resistance to the above com- mon corrosive agents, has made Steel and Iron exceptionally efficient materials for all kinds of table cutlery and culinary utensils. 44 FIRTH-sS TERDCULNG* SLE ED CO VE AN UNpoLisHeo PotlsHeO NICKEL STAINLESS. BLADES: BLAves WS 7 Cron fen SANE BS 5 ae Sie Ealy ie Mention has been made of the fact that Steel shows its highest resistance to stain when in the hard- ened or some modification of the hardened state. This rule applies to all cases, whether the hardness be due to a high quenching temperature or the result of a low tempering heat. Within reasonable limits, in which composition plays an important part, the harder the steel, the more resistant the surface. In the foregoing, mention has been made only of the application of Steel to common household articles and of its resistance to tarnishing agents met with in everyday life. However, its use is not limited to this narrow field. It has a very wide field of ap- plication to which it readily adapts itself as shown by its behavior with the following corrosive reagents :— Acetic Acid. Glacial Acetic-has no effect. Diluted to various strengths it attacks slightly. It is a remarkable fact that vinegar which contains 5% Acetic acid, has little or no effect upon properly hardened and polished Stainless Steel. Acetic Anhydride Acid. Attacks readily. Acetone. Slightly attacks the steel. Alcohol. The hardened steel is not appreciably at- tacked by ethyl alcohol or ordinary alcoholic beverages. Alkalies. Caustic alkalies have no effect whatever upon the steel. Alum. Strong solutions readily react upon the steel. 40° FIRTH-STERLING STEEL GOM P Awies SP ALENGIcE S Sane Sele enc 47 Aluminum Sulphate. Solutions of various strength attack the steel. Ammonia. Solutions of ammonia have no effect. Ammonium Chloride. Very marked corrosion. Ammonium Sulphate. Steel is readily attacked. Aqua Regia (3HC!l + HNO). Stainless steel offers very little resistance to this combination of acids, regardless of whether the steel is hardened or annealed. Baking Oven Gases. Very slignt tarnish. Benzene. No effect. Benzol. No effect. Blood. No corrosive action. Boric Acid. ‘The steel is unaffected by this acid in any degree of concentration. Calcium Chloride. Does not attack the steel in a saturated solution but dilute solutions have a slight effect. Carbon Tetrachloride. Like many corrosive agents, the pure liquid has no effect but dilute alcoholic solutions readily attack the steel. | Chloracetic Acid. Attacks the steel in all conditions. Chlorine. Either dry or moist chlorine gas readily attacks the steel. Chlorosulphonic Acid. Immersed specimens not visibly affected but acid reacts on steel with moist 48 . FIRTH-STERLING STEEL COMPANY GUIBAGIEN [a beS Gurus Ts EL 49 air and specimens partially immersed are attacked at level of the liquid. Citric Acid. ‘The steel is corroded in proportion to the strength of the acid. Lemon juice containing about 6% Citric Acid has no effect. Copper Chloride. Readily attacks the steel. Copper Sulphate. In a neutral solution, this salt does not appreciably affect the hardened steel. Dry Battery Compound (A mixture of zinc and am- monium chloride with manganese dioxide). Very marked corrosion takes place. Ferric Chloride. Readily attacks. Formic Acid. The steel is attacked to a limited degree. Gasoline. No effect. Glue. Not ordinarily effected. Hydrochloric Acid. Stainless Steel offers little re- sistance to this acid. Ink. Stainless Steel has been tested with various makes and colors of ink. Little effect has been noted, although in some cases the steel was stained slightly. Iodine. Corrodes but to a limited degree. Lactic Acid. Corrodes to a considerable degree. Sour milk, although high in Lactic acid content, does not attack the steel. Lemon Juice. No effect but steel is affected by Cit- ric Acid (See notes on vinegar and acetic acid). 50 FIRTH STERLUNG* SD PES COM ANe SIIPALON 1 & Sime Se REL 51 Lime. No effect whatever upon the steel. Lysol. No effect upon the steel. Magnesium Carbonate. A thick paste of this mate- rial was allowed to dry on the steel. No effect was noted. Menthol. Strong alcoholic solutions stain the steel in proportion to the degree of concentration. Mercuric Chloride. A marked corrosion takes place when strong solutions are used. Very dilute solu- tions, such as are used for surgical antiseptics, have little effect. Mercury. No attack whatever. Milk. Neither sweet nor sour milk affects the steel. see Lactic Acid. Monochloracetic Acid. Attacks readily. Nitric Acid. Practically no effect upon the steel. Boiling solutions of either dilute or concentrated acid do not attack it. Novocaine. To note its adaptability for hypodermic needles, the steel was immersed in a 1% solution of this substance for seven days. No appreciable effect was disclosed. Oils. Light or heavy lubricating oils, cylinder and paraffin oils have no effect. Oleic Acid. No effect upon the steel. Phosphoric Acid. A saturated solution has no effect. In various degrees of concentration, a slight gen- eral attack takes place. ies RFIREH-STERLING~S DEE ECO Vira BAL ASENG anes aees Et 53 Potassium Cyanide. No effect on the steel. Potassium Ferricyanide. Readily attacks the steel. Potassium Oxalate. No effect on the steel. Quinine Sulphate. Steel is noticeably pitted. Quinine Bisulphate. Steel is noticeably pitted. Rubber. Investigations made with apparatus meeting conditions in the vulcanizing of rubber indicate the steel is attacked due to Sulphur Chloride present. Silver Bromide. No attack offered by this salt. Sodium Chloride. Pitted locally by saturated solu- tion (pure). Sodium Salicylate. No noticeable effect. Sodium Sulphate. Strong solutions of this salt readily attack the steel. Soft Soap. Has no effect upon the steel. Steam. No corrosion offered unless considerable amounts of some salt or acid is in solution in the water. Stearic Acid. No effect upon the steel. Sugar. Totally unaffected by any strength of solution. Sulphur Chloride. In the presence of water or moisture, the steel is readily attacked by this cor- rosive chemical. Sulphuric Acid. Readily attacks in any degree of concentration. 54 FIR THeS TERE DNGYS TE EW -CO MPA ii Sulphurous Acid. Very similar in its reactions to sulphuric. Tannic Acid. Does not offer any attack but fumes cause a very slight stain. Tannin. Practically no effect. Thymol. Slightly stained by strong solutions. Trichloracetic Acid. Attacks immediately and action is very rapid. SPA TN EE SSo 5 LEE TERMS OF WARRANTY We will replace any steel which proves defective when properly worked and treated and used for the purpose specified in the Pict mp teio 1c ld) Metor labor or damages will be allowed. We cannot guar- antee resistance to corrosion unless we know the exact conditions under which steel is to be used. 55 SEAT INTIS Sens URED yi Index PAGE Acetic Acid - - : : ; : 2 45 Acetone” - : 2 : . 2 : 45 Acetylene mining eh petite - : - - = - 20 Air hardening Beep ety A : : ~ i 3 : 15 Alcohol — - - : : : . : : a 45 Alkalies - = : : : : : : a : 45 Alum - . : - : : : : : 45 Aluminum ainhate - - = - - : - 47 American Stainless Steel Company - - - - = 9 Ammonia - - - - : : : 5 A AY, Ammonium Chloride - - : : : ; : BLA 749 Analysis - - - - : : : : é : 25 Annealing - - - - - - - - =o a16 Annealed, ‘Darileneee - - : : : : z 13 Pel eaticns 3 : E : Z : : Hae Aqua Regia - - - = : : : - 47 Atmospheric corrosion - - - - - : - - 4] Battery Spoounds - : : : : : : : 49 Benzene - : : : : : a : z 47 Benzol - : : d é 7 if 47 Blue Chip High Speed Steel - - - - - - Av Boric Acid - : : , : : : 47 Brazing - - - - : . : 2 R 20 Brearley, Harry - : : : é : : - 2 9 Brinell hardness - : : Pel Omer: ooze) Bureau of Standards Tables 3 2 - : aE Sey es Calcium Chloride - : é : : i A7 Carbon Tetrachloride - - - 4 : a q ; 47 Case Hardening : : - 2 é : : : oN Caustics - - - : : zs : . i 45 Chemical Analysis - - “ : z : : : 25 Chlorine - - - : 2 : ‘ : is s 47 Chloracetic Acid - E = : 2 Z . 47 Chlorosulphonic Acid - = - = 2 “ . 47 Chromium - - - = : E 2 2 Beh OVP 5 7. Citric Acid . - - = < : : : 49 Coefficient of Expansion” - : : : : 32, 33, 34 58 FHIRTH-STERLIN G oSTLER EP COMPaay PAGE Cold Working - 2 - - - : , - - 2A Copper Chloride - - - - - - - - 49 Copper Sulphate - - - - - - - - 23, 49 Corrosion - 2 2 - - - : : : - ZF Corrosion, Atmospheric ; - . - - - 4] Corrosion, Metal : : A = : = - 2 43 Corrosion, Seats of = - “ = a = : - - 23 Cutlery = - - : - . = - - - ae a es be) Cutting Properties — - : : E “ = Stale : 39 Deep Drawing - - S - - - - - vA Discoloration at High Temperatures - , < : =5 18800 Drawing the Temper - - - - - - - 18 Dry Battery Compound — - - - = - - - 49 Dry Finishing - - - - - - - - - ao Electrical Conductivity 4 2 - : - - 36 Electrical Resistivity - < : : = - . : 36 Electrolytic action 2 4 2 - : : - 14, 23, 43 Etching a - - - - - - - - - Loe Expansion, Coefficient of - = - 4 : = S233, 4 Ferric Chloride - - - - - - - 20,23, 49 Finishing - - <7 2 ath 3s It, VA ae Firth-Sterling Macnee Steel - : : - - s7 Firth-Sterling Special Tool Steel - : : 5 - 3 37 Firth eo 0ns elstd ye nos : : - ‘ = Da16 Flux for brazing - - - - - E - : 20 Forging Iron - : - - - : - 19 Forging Steel - - - 2 - - - ie Formic Acid = - ; : - - - - : 49 Fruits - - - - - - - - : : 43 Galvanic, see Electrolytic Action Gasoline - - - - - - - - 2 - 49 Glue - - - - - - - - - = 49 Grinders-scorch ~ = 5 - - - - - : 22 Grinding - - - = - a ee - : . 22 Guarantee - : - - - - - - S : ee Hardening treatment - : - - - - - - 17 Hardness - : - - - - 7 ebay ale Hardness of Gales : 4 - - - - - - 39 Heat Curves” - - - - - - - - : 18 Heat Treatment = - - - - - - - 14,17 STU GIN Gey Oe 59 PAGE High Speed Steel 2 2 e 2 : : 3) ee pA ou oS, nastorye | = : : E 2 : : < : 9 Hot Stamping - - = - - - - - - 24 Hydrochloric Acid - - - - - - 23, 24, 49 Identification Marks - : 3 : 2 - E = Ee! Ink - - : a : : : “ : = : 49 Iodine - ‘ - - - - - - : - 49 Lactic Acid - - - ~ = - - - - 49 Lemon Juice’ - - - - - - - 2 “ 49 Lime - . : - = = - : : 51 Lye - - - g : ; - - 5 : : 43 Lysol : - : - - : : - : 2 Si! Machinability § - - : - - - - : : 13 Machining Properties - - - - - - - - 22 Magnesium Carbonate ~ : - - - - 2 Sul Magnetic Properties - - - - - - - - oy Meats - - - - - - - - 4 = 43 Melting Point - - - - - - - - - 39 Menthol - 4 - ~ - . - = 2 2 51 Mercury - - - . - - - - = : Di Mercuric Chlorid : - - - - - - : au Metal Corrosion - : - 4 = : - : 43 Milk - - * - - - = - : : Sil Modulus of Elasticity - - - - - - - 35 Monochloracetic Acid : - - : z - - 51 Nitric Acid - - - - - - - = 51 Momuauzing ~§-° - - - - - - - - 16 Novocaine - - - - - - - - : 3 51 Oils - = - - = - s - - : : 51 Oleic Acid - - - - - - - : 3 D | Oven Gases - - - - - = - - . 47 Oxidation, see Corrosion Oxide of Sulphur - a : 4 - : : 2 41 Particularly Annealed - : - - - : Sloe lt Patents - - - - - - - - - - 9 Permanent Magnets - - - - : - - - ey) Physical Properties - - - - . - - - 14,27 Phosphoric Acid : - 2 . - - - - BI Pickling - - - - - - - - “ - 24 Pickling Vinegar - - - - - - - ; 43 60:> “FIRTH-STERLING STRERL COM? Ana PAGE Polishing 2 “ = : _ : - a ee oat Purposes’ - : . . - : - : - 2 1] Possibilities : : - : : : - é : 11 Potassium Cyanide - - - - - - - - 53 Potassium Oxalate - z : = - - - 53 Properties at High Temperatures - - - : - Sy Quinine Sulphate - g : 5 : - - 53 Reduction Area - - 5 2 : : 2 21 28629 a0 Removal of Surface - . - : J : - 131421? ee Resistance to Heat - - - - - - - - 31 Rubber : : 5 7 : . - - : : 53 Rust, see Corrosion Scaling at High Temperatures - - - - - - 31 Scale in Stencil Marks - : ~ = = : - 24 Scorch, Grinders : : . - - - - - as Seats of Corrosion — - : : - : - - - 23 Sea Water : : - . - 2 : 2 : 4] Silver Bromide - 2 - - : - ; - : oye Iron? - - - - - = - - : 14 Smoke “ 2 “ : : - - = : 4] Sodium Chloride - - - eS = - - 53 Sodium Salicylate : _ - - : : 2 - 53 Sodium Sulphate - : . s 2 : - 53 Soft Soap - - : : : : = 5 - - a5 Soldering - ; s : “ : 2 c s 5 gee Solutions for Etching - . 5 7 - : : - 23 Solution for Pickling - - : : : - : - 24 Specific Gravity “2 = 3 - - : = - 37 Stainless Iron Discovery — - : = - = 2 é 10 Steam - - : : - - - : - 53 Stearic Acid : : : - - - “ . ae Stencil Marks - - - - - - = - 2 24 Sugar - : : - - - a 4 : 53 Sulphur China: - - - - =, as E : 53 Sulphuric Acid - - - : E - ane 53 Sulphurous Acid z - - - - - = : 54 Surface, removal of - : 2 - : ~ 13314, 212787 Tannic Acid : = : 2 z 2 : : 54 ‘Tannin e ‘ : 2 : : i 54 Temper Caloree - - - : : = : 5 ae O SATIN URES Stoel EES 61 PAGE ‘Tempering = - - - - - : : 2 18 Tensile Strength - 3 - - - : ey) ‘Terms of Warranty - - - 3 - : = - a5) ‘Thermal meescuotiy Cy. - - - - 7 é : 35 Ceiyvimol ea - - : - - : - - 54 Trichloracetic Acid - - - - - 2 : : 54 Types of Stainless Steel - - = 4 2 - - 13 Uses - : : - - : : : : eal ee Vegetables : - - - : - - - 5 43 Vinegar - : “ ‘ - : 2 = : 43 Warranty - - - - - - - - - oe) Weathering crs ia - - - - - - : 4] Welding - - - - - - - - - Z 20 Wet Finishing - - - : é = : : 22 Yield Point : - - - - - : te a PAY ee) Zinc Chloride - . : 7 - - - - - 21 ra ——— i 7 GETTY RESEARC rind. min ee te Se a a Sie SS SSE ea a ar = See oan wa La (Nae a ee He = Sane Semiahmoo a Sr Tae ee ess nas SSS = Se a a ee Sy eS a a Pe a ee Sse eee