摘要
为了提高SCX400车轮钢表面的强度,采用超声滚压技术对其表面进行了强化处理,并通过试验测试手段对其压力参数进行优化。结果表明:增大超声滚压力有助于获得更大厚度的变形层,靠近表面附近区域的组织存在强烈塑性变形,过渡区的变形程度减小,而内部组织则保持基本不变的状态。当施加100 N超声滚压时,在表层组织中生成了尺寸约为5 nm的纳米晶;继续提高滚压力到400 N,试样表层获得更高比例的非晶态组织,随着深度的增加,SCX400车轮钢的表面硬度表现出整体减小;将滚压力提高到300 N和400 N的情况下,距离表面50μm的组织硬度分别为371 HV和383 HV。表层残余压应力随超声滚压力的提高发生了持续升高,并且在增大滚压力的过程中,残余应力作用深度也发生了显著增大。完成超声滚压后,引起合金组织晶格的改变,并形成压缩残余应力。
In order to improve the surface strength of SCX400 wheel steel,ultrasonic rolling technology was used to strengthen the surface.The pressure parameters were optimized by means of experimental test.Results showed that increasing the ultrasonic rolling pressure was helpful to obtain the deformation layer with larger thickness.There was a strong plastic deformation in the tissue near the surface,and the deformation degree in the transition zone was decreased,while the internal microstructure remained basically unchanged.Nanocrystals with a size of about 5 nm were formed in the surface tissues when 100 N ultrasonic rolling was applied.As the rolling pressure continued to increase to 400 N,a higher proportion of amorphous microstructure was obtained on the surface of the sample.The surface hardness of SCX400 wheel steel was decreased as a whole with the increase of depth.When the rolling pressure was increased to 300 N and 400 N,the microhardness of the area 50μm from the surface was 371 HV and 383 HV,respectively.The residual compressive stress of surface layer was increased continuously with the increase of ultrasonic rolling pressure.In the process of increasing the rolling pressure,the depth of residual stress was also increased significantly.After the completion of ultrasonic rolling,the microstructure lattice of the alloy was changed,and the compressive residual stress was formed.
作者
李军
康皓
朱玉红
孙爽
LI Jun;KANG Hao;ZHU Yu-hong;SUN Shuang(School of Mechanical and Electrical Engineering,Tianjin Modern Vocational and Technical College,Tianjin 300350,China;School of Mechanical and Electrical Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Key Laboratory of Green Synthesis and Conversion of Ministry of Education,School of Chemical Engineering,Tianjin University,Tianjin 300072,China;Innovation College,Tianjin Vocational and Technical Normal University,Tianjin 300222,China)
出处
《材料保护》
CAS
CSCD
2021年第5期103-107,共5页
Materials Protection
基金
国家自然科学基金资助项目(20576098)
甘肃省科技厅项目(1610RJZA044)。
