Annealed condition: heat to 830 °C followed by slow cooling.( r4 r8 w- A1 O8 z! ^: c
退火:加热到830℃,缓慢冷却。 # g0 k0 K+ Z# y; O8 X; k( g7 q- Brinell Hardness: 170$ B" P& P X! H; o, G5 N
• Oil quench from 980 °C.(或空冷) Temper at 690 °C.( V- w. j. b* |2 k. ~4 s
油淬980℃,回火690℃