冷却速率对55CrSi弹簧钢的相变组织和显微硬度的影响

来源期刊：上海金属2010年第6期

论文作者：王晓峰 陈伟庆

文章页码：13 - 15

关键词：55SiCr弹簧钢； 珠光体； CCT曲线； 组织； 显微硬度

Key words：55SiCr Spring Steel； Pearlite； CCT Curve； Microstructure； Micro-Hardness

摘    要：针对55SiCr弹簧钢冷却转变过程的组织转变问题,测定了55SiCr弹簧钢的连续冷却转变曲线(CCT),采用金相显微镜及扫描电镜观察不同冷速下的显微组织,测定不同冷速下钢的显微硬度(HV)。结果表明:当冷却速率在1~3℃/s时,先析出铁素体和珠光体组织;随着冷却速率的增加,珠光体含量增加;当冷却速率达到5℃/s时,钢中珠光体含量达到最大值。因此,为了得到强韧性较高、性能优良、珠光体含量较高的产品,钢的冷却速率应控制在3~5℃/s左右。

Abstract: A continuous cooling transformation (CCT) curve of 55SiCr spring steel was tested by thermo mechanical simulator. The microstructure was analyzed at different cooling rates by SEM and microscope. The results showed that ferrite and pearlite precipitated firstly at the cooling rate of 1 ～ 3℃/s, the amount of pearlite increased as the cooling rate increasing. As the cooling rate increased to 5℃/s, the amount of pearlite reached the maximum. Therefore, in order to get a higher strength, toughness and excellent performance product with a higher pearlite amount, the cooling rate of the steel should be controlled within 3℃/s to 5℃/s.