Properties Of Alloy Steels
: ALLOYS AND THEIR EFFECT UPON STEEL: The Working Of Steel
The following table shows the percentages of carbon, manganese,
nickel, chromium and vanadium in typical steel alloys for engineering
purposes. It also gives the elastic limit, tensile strength, elongation
and reduction of area of the various alloys, all being given the same
heat treatment with a drawing temperature of 1,100 deg.F. (600 deg.C.). The
specimens were one inch rounds machined after heat treatment.
<
engineering construction steels and then usually in combination
with chromium. Tungsten is used principally for the magnets of
magnetos, to some extent in the manufacture of hacksaws, and for
special tool steels.
TABLE I.--PROPERTIES OF ALLOY STEELS
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\Manganese,/ \Chromium,/ ElasticTensile ElongationReduction
Carbon,\ per /Nickel,\ per /Vanadium,limit, Strength,in 2 in., of area,
per cent per cent per cent lb. perlb. per per cent per cent
cent cent sq. in.sq. in.
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0.27 0.55 49,000 80,000 30 65
0.27 0.47 0.26 66,000 98,000 25 52
0.36 0.42 58,000 90,000 27 60
0.34 0.87 0.13 82,500 103,000 22 57
0.45 0.50 65,000 96,000 22 52
0.43 0.60 0.32 96,000 122,000 21 52
0.47 0.90 0.15 102,000 127,500 23 58
0.30 0.60 3.40 75,000 105,000 25 67
0.33 0.63 3.60 0.25 118,000 142,000 17 57
0.30 0.49 3.60 1.70 119,000 149,500 21 60
0.25 0.47 3.47 1.60 0.15 139,000 170,000 18 53
0.25 0.50 2.00 1.00 102,000 124,000 25 70
0.38 0.30 2.08 1.16 120,000 134,000 20 57
0.42 0.22 2.14 1.27 0.26 145,000 161,500 16 53
0.36 0.61 1.46 0.64 117,600 132,500 16 58
0.36 0.50 1.30 0.75 0.16 140,000 157,500 17 54
0.30 0.50 0.80 90,000 105,000 20 50
0.23 0.58 0.82 0.17 106,000 124,000 21 66
0.26 0.48 0.92 0.20 112,000 137,000 20 61
0.35 0.64 1.03 0.22 132,500 149,500 16 54
0.50 0.92 1.02 0.20 170,000 186,000 15 45
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More
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High-chromium Or Rust-proof Steel
High-chromium, or what is called stainless steel containing from 11 to 14 per cent chromium, was originally developed for cutlery purposes, but has in the past few years been used to a considerable extent for exhaust valves in airplane engines becau... Highly Stressed Parts
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TO FORGE.--Gently warm the steel to remove any chill is particularly desirable in the winter. Then heat slowly and carefully to a scaling heat, that is a lemon heat (1,800 deg.-2,000 deg.F.), and forge uniformly. Reheat the tool for further forging ... Leeds And Northrup Optical Pyrometer
The principles of this very popular method of measuring temperature are sketched in Fig. 123. The instrument is light and portable, and can be sighted as easily as an opera glass. The telescope, which is held in the hand, weighs only 25 oz.;... Liberty Motor Connecting Rods
The requirements for materials for the Liberty motor connecting rods are so severe that the methods of securing the desired qualities will be of value in other lines. The original specifications called for chrome-nickel but the losses due to the dif... Machineability
Reheating for machine ability was done at 100 deg. less than the drawing temperature, but the time of soaking is more than double. After both drawing and reheating, the blanks were buried in lime where they remain, out of contact with the air, until... Making Steel Balls
Steel balls are made from rods or coils according to size, stock less than 9/16-in. comes in coils. Stock 5/8-in. and larger comes in rods. Ball stock is designated in thousandths so that 5/8-in. rods are known as 0.625-in. stock. Steel for makin... Manganese
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Phosphorus is one of the impurities in steel, and it has been the object of steel makers for years to eliminate it. On cheap grades of steel, not subject to any abnormal strain or stress, 0.1 per cent phosphorus is not objectionable. High phosphorus... Pickling The Forgings
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The piston pin on an aviation engine must possess maximum resistance to wear and to fatigue. For this reason, the piston pin is considered, from a metallurgical standpoint, the most important part on the engine to produce in quantities and still pos... Placing Of Pyrometers
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The following table shows the percentages of carbon, manganese, nickel, chromium and vanadium in typical steel alloys for engineering purposes. It also gives the elastic limit, tensile strength, elongation and reduction of area of the various alloys... Properties Of Steel
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The effect of heat treatment on overheated steel is shown graphically in Fig. 65 to the series of illustrations on pages 137 to 144. This was prepared by Thos. Firth & Sons, Ltd., Sheffield, England. The center piece Fig. 65 represents a block ... Robert Mushet
Robert (Forester) Mushet (1811-1891), born in the Forest of Dean, Gloucestershire, of a Scots father (David, 1772-1847) himself a noted contributor to the metallurgy of iron and steel, is, like the American William Kelly, considered by many to have ... S A E Heat Treatments
The Society of Automotive Engineers have adopted certain heat treatments to suit different steels and varying conditions. These have already been referred to on pages 39 to 41 in connection with the different steels used in automobile practice. Thes... Separating The Work From The Compound
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In the new method, the packed pots are run into the case-hardening furnaces, which are heated to 1,600 deg.F. On the insertion of the cold pots, the temperature naturally falls. The amount of this fall is dependent upon a number of variables, but i... Shrinking And Enlarging Work
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