脉冲等离子爆炸工艺表面改性H13钢

 为研究脉冲等离子爆炸工艺制备H13钢(4Cr5MoSiV1)表面改性层的组织和性能，通过对显微组织形貌、相结构、残余应力、硬度和耐磨性的分析，对脉冲等离子爆炸工艺的改性机制和影响进行了讨论。结果表明，脉冲等离子爆炸工艺使H13钢表面发生快速熔凝和快速淬火过程，在材料表面形成厚度均匀、组织致密、高硬度的改性层；改性层中马氏体细化，同时由于不同物理变化过程分别形成残余奥氏体和逆变奥氏体；随着脉冲次数的增加，材料表面的残余应力经历了由压应力先增大后减小然后转变成拉应力的过程；改性层的厚度和硬度随脉冲次数的增加而提高，但同时表面熔化程度加剧，表层低硬度熔凝区厚度增加。当脉冲次数为8次时，H13钢具有最优的耐磨损性能。

Surface modification of H13 steel by pulse-plasma detonation treatment

Effects of pulse-plasma detonation technique on microstructure and performance of H13 steel (4Cr5MoSiV1) were studied. Base on the research of microstructure,phase structure,surface residual stress,micro-hardness and wear resistance,the mechanism of surface modification and the effect of pulse-plasma detonation technique were analyzed and discussed. The results indicate that the modified layer with uniform thickness,compact structure and high hardness is obtained on the surface of H13 steel as a result of rapid solidification and rapid quenching. Martensite is refined in the modified layer,and the residual austenite and reversed austenite are formed with different physical processes. With the increase of treatment pulses,the residual compressive stress in material surface first increases,and then decreases and fi-nally changes to tensile stress. The thickness and micro-hardness of modified layer improves with the increase of treat-ment pulses,while the surface melting is intensified and the melting zone becomes thicken. The greatest enhancement of wear resistance occurs when the number of treatment pulses is 8.