在VDBF-250真空热压烧结炉中,采用真空热压烧结工艺制备了10%(体积分数)TiC/Cu-Al2 O3复合材料。利用 Gleeble-1500热力模拟实验机,在温度为450~850℃、应变速率为0.001~1 s-1、真应变量0.7的条件下,对10%(体积分数)TiC/Cu-Al2 O3复合材料高温塑性变形过程中的动态再结晶行为及其热加工图进行研究和分析。结果表明,该材料烧结态致密度为98.53%,显微硬度为158 HV,导电率为48.7% IACS;材料的高温流变应力-应变曲线主要以动态再结晶软化机制为特征,峰值应力随变形温度的降低或应变速率的升高而增加,属于温度和应变速率敏感材料;同时,利用10%(体积分数)TiC/Cu-Al2 O3复合材料 DMM 加工图分析了其变形机制和失稳机制,并最终确定了热加工工艺参数选取范围为变形温度750~850℃,应变速率0.01~0.1 s-1。
In VDBF-250 vacuum hot pressing sintering furnace,10vol% TiC/Cu-Al2 O3 composite was prepared by vacuum-pressed sintering.Using the Gleeble-1500D simulator,the high-temperature plastic deformation be-havior and processing map of 10vol% TiC/Cu-Al2 O3 composite was investigated at 450-850 ℃ with the strain rate of 0.001-1 s-1 and total strain of 0.7.The results show that the density,microhardness and electrical con-ductivity of the composite are 98.53%,158 HV and 48.7% IACS.The softening mechanism of the dynamic re-crystallization was a feature of high-temperature flow stress-strain curves of the composites,and the peak stress increased with the decrease of deformation temperature or the increase of strain rate,and belong to temperature and strain rate sensitive material.Meanwhile,the obtained processing map of dynamic material modeling was used to analyze the deformation mechanism and the destabilization mechanism of 10vol% TiC/Cu-Al2 O3 com-posite,the optimal deformation processing parameters of the deformation temperatures range and the strain rates range were 750-850 ℃ and 0.01-0.1 s-1 .