Alloy Steel Castings Table 8

TABLE 8 - Recommendations for Heat Treating Castings ¹
GRADE	Annealing			Normalizing & Tempering ²				Quench Hardening			Tempering after Quenching ²			Stress Relieving
	Temp. +/-25^oF	Time ³ at Temp.	Method of Cooling	Temp. +/-25^oF	Time ³ at Temp.	Method of Cooling	Minimum Tempering Temp (^oF)	Temp. +/-25^oF	Time ³ at Temp.	Method of Cooling	Min. Temp. ⁵ (^oF)	Time ³ at Temp.	Method of Cooling	Temp (^oF)	Time ³ at Temp.	Method of Cooling
Moly-Telastic	1600	45-60	Furnace Cool to below 850^oF	1600	45-60	Air	1000	1575	45-60	Water ⁶ or Oil ⁴	900	45-60	Air or Furnace	See Note ⁷	45	Air or Furnace
No. 1 Gearalloy	1600	45-60	Furnace Cool to below 850^oF	1575	45-60	Air	1000	1575	45-60	Water ⁸ or Oil ⁴	900	45-60	Air or Furnace	See Note ⁷	45	Air or Furnace
No. 2 Gearalloy	1700	45-60	Furnace Cool to below 850^oF	1700	45-60	Air	. . .	1700	45-60	Water	1000	45-60	Air or Furnace	See Note ⁷	45	Air or Furnace
No. 3 Gearalloy	1600	45-60	Furnace Cool to below 850^oF	1575	45-60	Air	1000	1575	45-60	Oil ⁹	900	45-60	Air or Furnace	See Note ⁷	45	Air or Furnace
No. 4 Gearalloy	1600	45-60	Furnace Cool to below 850^oF	1525	45-60	Air	1000	1500	45-60	Oil ⁹	900	45-60	Air or Furnace	See Note ⁷	45	Air or Furnace
No. 6 Gearalloy	1600	45-60	Furnace Cool to below 850^oF	1525	45-60	Air	1000	. . .	. . .	See Note ¹⁰	. . .	. . .	. . .	See Note ⁷	45	Air or Furnace
¹ Tempering temperatures vary depending upon specified hardness, chemical analysis, and controlling section size.
Falk will provide information and recommendations for any particular customer heat treatment application upon request.
² Time at temperature and method of cooling for tempering after normalizing, shall be the same as for tempering after quench hardening.
³ Minutes/Inch of maximum section at temperature, depends upon accuracy (condition) and temperature variance of the furnace.
Forty-five Minutes/Inch hold time may be used with more accurate and uniform furnaces.
⁴ Oil or equivalent synthetic quenching is used when design considerations increase susceptibility to quench cracking.
⁵ Use highest possible tempering temperature to obtain specified hardness and/or mechanical properties.
⁶ Moly-Telasic is primarily hardened by water quenching (130o-140^oF).
⁷ 1100^oF or 50-100^oF below tempering temperature, whichever is less.
⁸ No. 1 Gearalloy is commonly hot water quenched (130-180^oF).
⁹ Oil or equivalent synthetic quenchant.
¹⁰ No. 6 Gearalloy is not recommended for quench hardening.