S7 Tool Steel
Chemical Analysis: | |
---|---|
Carbon | .45/.50 |
Manganese | .20/.80 |
Phosphorus | .030 Max. |
Sulfur | .030 Max. |
Silicon | .20/1.00 |
Chromium | 3.00/3.50 |
Vanadium | .35 Max. |
Tungsten | ------- |
Molybdenum | 1.30/1.80 |
Cobalt | ------- |
Tempering Temp. º(F): | Hardness Rc |
---|---|
As-quenched | 60.0 |
400 | 58.0 |
500 | 56.0 |
600 | 55.0 |
700 | 54.0 |
800 | 53.0 |
900 | 52.0 |
1000 | 51.0 |
1100 | 47.0 |
1200 | 38.0 |
1300 | 31.0 |
Uses:
Punches, dies, plastic molds, chisels, gripper dies, engraving dies, bending dies, shear blades, slitter knives, rivet sets.
Forging/Rolling:
Preheat to 1200° F - 1300° F and soak thoroughly. Then raise to 2000° F - 2050° F. Do not forge or roll below 1700° F, cool slowly from the forging or rolling temperature. Do not normalize.
Annealing:
Heat in the 1500° F - 1550° F range, and hold for uniformity. Furnace cool slowly to 1000° F and air cool. Expected Brinell hardness 197 max.
Hardening:
Preheat to 1200° F - 1300° F, soak until uniformly heated, and either transfer or raise furnace temperature to 1725° F, and hold 1 hour per inch of greatest thickness. Sections 2-1/2" or less should be quenched in still air to 150° F. Section sizes 2-1/2" to 6" can be oil quenched to black, but section sizes over 6" should not be full oil quenched..
Tempering:
Temper immediately after quenching, before parts have cooled to below 150° F. Parts should always be held a minimum of 2 hours per inch of greatest thickness. Double tempering is recommended. For cold work and similar applications a tempering temperature of 400° F - 500° F is suggested and 900° F - 1000° F for hot work applications. The above tempering table may be used as a guide. However, since 1/2" dia. specimens were used for this test, it may be found that heavier sections are several points lower.