【摘要】 通过光学显微镜(OM)、扫描电镜(SEM)观察及硬度测试,研究了加热温度和保温时间对轴承钢GCr15Si Mn碳化物回溶的影响。结果表明,随加热温度升高和保温时间延长,碳化物回溶加剧,组织显微硬度升高,且加热温度影响较保温时间更为明显;碳化物形态变化趋势为:层片状(或网状)→杆棒状→球状,部分完全溶入基体,但在实验条件下碳化物不能完全回溶;奥氏体优先在铁素体和渗碳体两相界面处形核,层片状珠光体向奥氏体转变过程极其快速。更多还原

【Abstract】 Effect of heating temperature and holding time on carbide dissolution of GCr15 Si Mn bearing steel was investigated by means of optical microscope( OM),scanning electron microscopy( SEM) and hardness test. The results show that with the increasing heating temperature and holding time,carbide dissolution intensifies and hardness increases,and the effect of heating temperature is greater than that of holding time. The evolution trend of carbide morphology is lamellar( or mesh),rod-shaped,spheroidal,and finally dissolving into the austenitic matrix,but carbide can not dissolve completely under the experimental conditions. Austenite preferentially nucleates at the ferrite / cementite interface,and the transformation of lamellar pearlite to austenite is extremely fast.更多还原