PAG淬火介质温度对60Si2CrVAT弹簧钢力学性能的影响

Effect of PAG quenchant temperature on mechanical properties of 60Si2CrVAT spring steel

采用KHR-A便携式冷却介质性能检测仪对不同温度13%PAG淬火介质的淬火冷却性能进行了测量,研究了60Si2Cr VAT弹簧钢经不同温度13%PAG介质淬火后显微组织及力学性能的变化。结果表明:不同温度13%PAG对冷速的影响主要体现在高温阶段即未发生马氏体转变前的温度段,而在低温阶段冷速相差较小,且冷速随介质温度升高而降低。弹簧钢热处理试验表明,随介质温度升高,淬火后残留奥氏体量增加;经440℃回火后,马氏体板条块显现地越明显,尺寸增大,马氏体板条宽度也随之增加;硬度、抗拉强度呈减小趋势,塑性增加。

The cooling characteristic of 13% PAG at different temperatures was measured using KHR-A equipment,and the effect of the quenchant temperature on microstructure and mechanical properties of 60Si2 Cr VAT spring steel was studied. The results show that the influence of quenchant temperature on cooling rate is mainly reflected in the high temperature phase, i. e. higher than matensite transformation temperature,and the cooling rate decreases as the temperature of the PAG increases. 60Si2 Cr VAT spring steel heat treatment experiments indicate that with the increase of the temperature of the medium,retained austenite content increased after quenching. After tempering,martensite block appears more obviously,and increases in size,as well as martensite lath width. The hardness and the tensile strength decrease while the plastic increases.