磨料水射流喷丸对渗碳GDL-1钢表面性能及残余应力场热松弛行为研究

发布时间：2018-02-16 12:06

本文关键词： 钢磨料水射流喷丸表面性能残余应力热松弛　出处：《机械工程学报》2017年22期 　论文类型：期刊论文

【摘要】：采用后混合磨料水射流喷丸对经渗碳风冷后的GDL-1钢进行表面强化与改性,通过激光共聚焦显微镜,扫描电镜,透射电镜,显微硬度仪,X射线应力衍射仪分析不同压力水喷后试样表面粗糙度、组织、硬度和残余应力等的变化规律,并研究300 MPa水喷处理后不同保温温度和保温时间残余应力场的热松弛行为。结果表明:随着水压的增加,表面粗糙度增大、残留奥氏体转变量增多、硬度提高幅度变大,水喷后,晶粒和组织得到明显细化,并且在表层形成一定深度的残余压应力场。残余应力的热松弛主要受保温时间和温度的影响,在100℃和300℃时,残余应力的热松弛受回复过程控制,500℃时,残余应力热松弛受回复和再结晶过程控制。表面残余应力在回复过程中存在两个阶段,初始阶段应力松弛速度快,以点缺陷回复为主,后一阶段松弛速率慢,以位错回复为主,并进一步研究指出Zener-Wert-Avrami方程并不适合描述整个回复过程。
[Abstract]:Using mixed abrasive water jet peening on GDL-1 steel with carburizing cooling the surface strengthening and modification by laser confocal microscopy, scanning electron microscopy, transmission electron microscopy, micro hardness tester, X ray analysis of different water pressure after spraying the surface roughness of the organization, power diffraction, variation of hardness and residual stress the stress relaxation behavior of MPa and 300 water spraying treatment after different heat preservation temperature and holding time, the residual stress field. The results showed that with the increase in water pressure, increase of surface roughness, residual austenite increased, the hardness increase becomes large, water spray, grain size and microstructures are refined and residual and a certain depth in the formation of the surface compressive stress field. The thermal relaxation of the residual stress is mainly affected by the holding time and temperature, in 100 degrees and 300 degrees, the thermal relaxation of the residual stress by the recovery process control, 500 DEG C, residual stress Thermal stress relaxation by recovery and recrystallization process control. The residual stress on the surface there are two stages in the recovery process, the initial stage of the stress relaxation speed, with point defects recovery, after a period of slow relaxation rate, the recovery of dislocation, and further pointed out that the Zener-Wert-Avrami equation is not suitable to describe the whole process of recovery.

【作者单位】：贵州大学材料与冶金学院;贵州大学贵州省材料结构与强度重点实验室;贵州大学贵州省高性能金属结构材料与制造技术工程实验室;贵州大学高性能金属结构材料与制造技术国家地方联合工程实验室;
【基金】：国家自然科学基金(51461006) 贵州省科技计划(黔科合JZ字[2014]2003,黔科合重大专项字(2014)6012)资助项目
【分类号】：TG178

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