Table 4. Classification, Approximate Compositions, and Properties Affecting Selection of Tool and Die Steels (From SAE Recommended Practice) Type of Tool Steel Chemical Composition a Non- warping Prop. Safety in Hardening Tough ness Depth of Hardening Wear Resistance C Mn Si Cr V W Mo Co High Speed Tungsten, 18-4-1 0.70 0.30 0.30 4.10 1.10 18.00 … … Good Good Poor Through Good Tungsten, 18-4-2 0.80 0.30 0.30 4.10 2.10 18.50 0.80 … Good Good Poor Through Good Tungsten, 18-4-3 1.05 0.30 0.30 4.10 3.25 18.50 0.70 … Good Good Poor Through Best Cobalt-Tungsten, 14-4-2-5 0.80 0.30 0.30 4.10 2.00 14.00 0.80 5.00 Good Fair Poor Through Good Cobalt-Tungsten, 18-4-1-5 0.75 0.30 0.30 4.10 1.00 18.00 0.80 5.00 Good Fair Poor Through Good Cobalt-Tungsten, 18-4-2-8 0.80 0.30 0.30 4.10 1.75 18.50 0.80 8.00 Good Fair Poor Through Good Cobalt-Tungsten, 18-4-2-12 0.80 0.30 0.30 4.10 1.75 20.00 0.80 12.00 Good Fair Poor Through Good Molybdenum, 8-2-1 0.80 0.30 0.30 4.00 1.15 1.50 8.50 … Good Fair Poor Through Good Molybdenum-Tungsten, 6-6-2 0.83 0.30 0.30 4.10 1.90 6.25 5.00 … Good Fair Poor Through Good Molybdenum-Tungsten, 6-6-3 1.15 0.30 0.30 4.10 3.25 5.75 5.25 … Good Fair Poor Through Best Molybdenum-Tungsten, 6-6-4 1.30 0.30 0.30 4.25 4.25 5.75 5.25 … Good Fair Poor Through Best Cobalt-Molybdenum-Tungsten, 6-6-2-8 0.85 0.30 0.30 4.10 2.00 6.00 5.00 8.00 Good Fair Poor Through Good a C = carbon; Mn = manganese; Si = silicon; Cr = chromium; V = vanadium; W = tungsten; Mo = molybdenum; Co = cobalt. b Carbon tool steels are usually available in four grades or qualities: Special (Grade 1) —The highest quality water-hardening carbon tool steel, controlled for hardenability, chemistry held to closest limits, and subject to rigid tests to ensure maximum uniformity in performance; Extra (Grade 2) —A high-quality water-hardening carbon tool steel, controlled for hardenability, subject to tests to ensure good service; Standard (Grade 3) —A good-quality water-hardening carbon tool steel, not controlled for hardenability, recommended for application where some latitude with respect to uniformity is permissible; Commercial (Grade 4) —A commercial-quality water-hardening carbon tool steel, not controlled for hardenability, not subject to special tests. On special and extra grades, limits on manganese, silicon, and chromium are not generally required if Shepherd hardenability limits are specified. For standard and commercial grades, limits are 0.35 max. each for Mn and Si; 0.15 max. Cr for standard; 0.20 max. Cr for commercial. c Toughness decreases somewhat when increasing depth of hardening. d Optional element. Steels have found satisfactory application either with or without the element present. In silicon-manganese steel listed under Shock-Resisting, if chromium, vanadium, and molybdenum are not present, then hardenability will be affected. e This steel may have 0.50 percent nickel as an optional element. The steel has been found to give satisfactory application either with or without the element present. Table 4. (Continued) Classification, Approximate Compositions, and Properties Affecting Selection of Tool and Die Steels
f Approximate nickel content of this steel is 1.50 percent. g Poor when water-quenched, fair when oil-quenched. h Poor when water-quenched, good when oil-quenched.
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