Machinery's Handbook, 31st Edition
MATERIALS FOR IRON AND STEEL CASTING 1483 condition) range from 40,000 to 70,000 pounds per square inch (276–483 MPa). Medium-carbon steel castings have a carbon content of from 0.20 to 0.50 percent. Other elements present are manganese, 0.50 to 1.00 percent; silicon, 0.20 to 0.80 percent; phos- phorus, 0.05 percent max.; and sulfur, 0.06 percent max. Their tensile strengths range from 65,000 to 105,000 pounds per square inch (448–724 MPa) depending, in part, upon heat treatment. High-carbon steel castings have a carbon content of more than 0.50 per- cent and also contain: manganese, 0.50 to 1.00 percent; silicon, 0.20 to 0.70 percent; and phosphorus and sulfur, 0.05 percent max. each. Fully annealed high-carbon steel castings exhibit tensile strengths of from 95,000 to 125,000 pounds per square inch (655–125 MPa). See Table 1 for grades and properties of carbon steel castings. Table 1. Mechanical Properties of Steel Castings Tensile
Yield Point, ksi (MPa)
Brinell Hardness Number
Type of Heat Treatment
Application Indicating Properties
Strength, ksi (MPa)
Structural Grades of Carbon Steel Castings
Low electric resistivity. Desirable magnetic properties. Carburizing and case hardening grades. Weldability. Good weldability. Medium strength with good machinability and high ductility. High strength carbon steels with good machinability, toughness and good fatigue resistance. Good weldability. Medium strength with high toughness and good machinability. For high temperature service. Certain steels of these classes have good high temperature properties and deep hardening properties. Toughness. Impact resistance. Good low temperature properties for certain steels. Deep hardening. Good combination of strength and toughness. Wear resistance. Hardness. Deep hardening. High strength. Wear and fatigue resistance. High strength and hardness. Wear resistance. High fatigue resistance.
60 (414)
30 (207)
32
120 Annealed
65 (448) 70 (483) 80 (552) 85 (586) 100 (689) 70 (483) 80 (552) 90 (621) 100 (689) 110 (758)
35 (241) 38 (262) 45 (310) 50 (345) 70 (483) 45 (310) 50 (345) 60 (414) 68 (469) 85 (586)
30 28 26 24 20 26 24 22 20 20
130 Normalized 140 Normalized
160 175 200
Normalized and tempered
Quenched and tempered
Engineering Grades of Low-Alloy Steel Castings
150 170 190 209 235
Normalized and tempered
Normalized and tempered a
Quenched and tempered
120 (827)
95 (655)
16
245
150 (1034) 175 (1207) 200 (1379)
125 (862) 148 (1020) 170 (1172)
12
300 340
Quenched and tempered
8 5
Quenched and tempered
400 a Quench and temper heat treatments may also be employed for these classes. ksi = kips per square inch = 1000s of pounds per square inch; MPa = megapascals. The data in the table above is for general information purposes only and not for use as design or specification limit values. The values listed above have been compiled by the Steel Founders’ Society of America as those normally expected in the production of steel castings. The castings are classified according to tensile strength values which are given in the first column. Specifications covering steel castings are prepared by the American Society for Testing and Materials, the Association of American Railroads, the Society of Automotive Engineers, the United States government (federal and military specifications), etc. Refer to publications issued by these organizations for these specifications. Alloy Steel Castings.— Alloy cast steels are those in which special alloying elements such as manganese, chromium, nickel, molybdenum, or vanadium have been added in sufficient quantities to obtain or increase certain desirable properties. Alloy cast steels are comprised of two groups—the low-alloy steels with their alloy content totaling less than 8 percent and the high-alloy steels with their alloy content totaling 8 percent or more. The addition of these various alloying elements in conjunction with suitable heat treatments, makes it pos- sible to secure steel castings having a wide range of properties. The three accompanying tables give information on these steels. The lower portion of Table 1 gives the engineering grades of low-alloy cast steels grouped according to tensile strengths and gives properties normally expected in the production of steel castings. Table 2 and Table 3 give the standard
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