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根据强流脉冲电子束表面合金化的特点,建立了相应的数学物理模型,以3Cr2W8V模具材料为基体,以Al为合金化元素,对电子束照射材料表面所产的热应力进行了数值模拟,并将数值模拟分析结果与实验结果进行了对比分析,结果表明:有限元模拟显示3Cr2W8V电子束合金化Al样品(Al层厚度t=2μm)冷却后的表层4μm范围内的点残余拉应力达到材料的屈服极限750 MPa,理论上材料将发生屈服。通过金相观察,样品表面有大量熔坑形貌,但并未出现明显裂纹,说明3Cr2W8V样品表面屈服形式主要为熔坑。另外,3Cr2W8V材料表层10μm范围内主要受残余拉应力,残余拉应力大小约为650～750 MPa。随着深度的增加,残余拉应力值急剧减小,并在距离表层20μm处受最大残余压应力,最大残余压应力值约为120 MPa,并随着深度的继续增加,残余压应力值缓慢减小。
According to the characteristics of the surface alloying of intense pulsed electron beam, the corresponding mathematical physics model was established. Based on the 3Cr2W8V mold material and Al as the alloying element, the thermal stress on the electron beam irradiated surface was numerically simulated. The numerical simulation results are compared with the experimental results. The results show that the finite element simulation shows that the residual tensile stress at 4μm in the surface layer of 3Cr2W8V electron beam alloyed Al samples (Al layer thickness t = 2μm) The yield point of 750 MPa, in theory, the material will yield. Metallographic observation shows that there are a lot of crater morphology on the surface of the sample, but no obvious cracks appear, which indicates that the yielding surface of 3Cr2W8V sample is mainly crater. In addition, 3Cr2W8V material surface mainly within the 10μm residual tensile stress, residual tensile stress is about 650 ~ 750 MPa. With the increase of depth, the residual tensile stress decreases sharply, and the maximum residual compressive stress is about 120 MPa at the depth of 20 μm from the surface. With the depth increasing, the residual compressive stress decreases slowly small.