GCr15轴承钢球化退火工艺

Spheroidizing annealing technology for GCr15 bearing steel

钢丝获得细粒状珠光体组织最有效的途径是球化退火。按照标准规定的目标制定轴承钢球化退火工艺:材料选择GCr15热轧酸洗盘条;退火设备采用从韩国引进的辊底式短周期保护气氛热处理炉(STC炉),炉内温度精度控制在±5℃之内。选择2种工艺进行试验,对处理后的GCr15热轧酸洗盘条分别进行力学性能和金相显微组织分析比较。结果表明,2种工艺均能够达到设计目标,但工艺1(热装炉升温到795℃,保温7 h,快速冷却到720℃,保温5 h,以20℃/h冷却速度降至650℃出炉)球化效果更佳,可以用于初期生产。

The most effective way for steel wire to get fine spheroidal pearlite is spheroidizing annealing. According to the goal standard formulated to set beating steel spheroidizing process, to select GCrl5 hot rolling pickling wire rod as raw ma terial, use roller-hearth type short period protective atmosphere heat treatment furnace imported from the South Korea, en sure the temperature in furnace to be controlled within ± 5 ℃. Selecting two kinds of process to do experiment, analyze and compare mechanical properties and metallographic structure of GCrl5 hot rolling wire rod after pickling, the results indica ted that the two process all reached design goal. The No. 1 process（ hot charging heating to 795 ℃, heat preservation 7 h, cooling to 720 ℃ fastly, heat preservation 5 h, cooling to 650 ℃ at the speed of 20 ℃/h, then draw a charge） has better effect, it can be used to initial production.