表面处理对高温合金 DZ40M 再结晶的影响

摘要

In order to evaluate the extent of plastic deformation and high-temperature recrystallization after different surface treat-ments,directionally solidified superalloy DZ40M was impacted by cold spray particles and also by grit blasting.The treated sam-ples were heat treated at 1 000 ℃ and 1 100 ℃ and the interaction of recrystal grain with precipitated carbide was investigated. The effects of the surface treatment on the thickness of plastic deformation and recrystallization layers were also studied.The results show that recrystal regions can be observed after surface treatments of both cold spray impacting and grit blasting on the surface of DZ40M after heat treated at 1 000 ℃ and 1 100 ℃.The precipitated carbide during heat-treating restrains the recrystal grain to some extent.The thickness and micro hardness of the plastic deformation layer by CoNiCrAlY particle impacting are much lower than that by grit blasting,which resulted in a thinner recrystal layer on the surface of DZ40M.The temperature has a significant effect on the thickness of the recrystal layer in regard to cold spray impacting treatment.The annealing can partially eliminate the work hardening of plastic deformation layers,but has no obvious influence on their thickness.%为了评价不同表面处理后 DZ40M 定向凝固高温合金表面塑性变形及高温再结晶程度，为表面处理工艺和参数选择提供依据，采用冷喷涂粒子冲击和喷砂对高温合金表面进行处理，经过1000和1100℃保温处理，考察了合金析出碳化物和表面再结晶的相互作用，并分析了表面处理方法对合金表面塑性层和再结晶层深度的影响。结果表明：冷喷涂粒子冲击和喷砂处理后的 DZ40M 高温合金在1000和1100℃下热处理后，表面均形成再结晶层；热处理时的二次析出碳化物对再结晶晶粒有一定的抑制作用；冷喷涂 CoNiCrAlY 粒子冲击后，合金表面塑性变形层的深度和维氏硬度均远低于喷砂处理的，其再结晶层厚度较小；冷喷涂 CoNiCrAlY 粒子冲击后的合金表面再结晶层厚度受热处理温度影响显著；退火可部分降低合金表面塑性层的加工硬化程度，但对塑性变形层深度无明显影响。