Effect of Cyclic Cryogenic Treatment on Wear Resistance, Impact Toughness, and Microstructure of 42CrMo Steel and Its Optimization

Table 3

The L₉ (3⁴) orthogonal array of cryogenic treatment.

Exp. no.	Cryogenic temperature/(°C)	Holding time/(h)	Cycles number
CT1	−120	2	1
CT2	−120	12	2
CT3	−120	24	3
CT4	−160	2	2
CT5	−160	12	3
CT6	−160	24	1
CT7	−196	2	3
CT8	−196	12	1
CT9	−196	24	2