S7 Tool Steel
|Tempering Temp. º(F):||Hardness Rc|
Punches, dies, plastic molds, chisels, gripper dies, engraving dies, bending dies, shear blades, slitter knives, rivet sets.
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.
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.
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..
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.