置氢对Ti-6Al-4V合金高温塑性变形的影响  

Effect of Hydrogenation on the Hot Deformation of Ti-6Al-4V Alloy

作　　者：牛勇[1] 李晓华[2] 王耀奇[2] 侯红亮[2] 李淼泉[1] 林莺莺[1] 李志强[2] 

机构地区：[1]西北工业大学,陕西西安710072 [2]北京航空制造工程研究所,北京100024

出　　处：《稀有金属材料与工程》2008年第12期2089-2093,共5页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(50371068);航空基金(05H53058)

摘　　要：利用XRD分析了置氢Ti-6Al-4V合金的相组成,应用Gleeble等温热模拟试验研究了置氢量对Ti-6Al-4V合金高温塑性变形的影响,计算了不同置氢量钛合金的变形激活能。结果表明:随置氢量的增加,Ti-6Al-4V合金β相含量增加,高温塑性变形的流动应力显著降低呈下凹型曲线变化,即存在一个最小值,应力最小值对应的置氢量随变形温度的升高而降低;置氢可以促进高温塑性变形过程动态软化与硬化的平衡;在相同应力水平下,适量的置氢可使变形温度降低50℃,或应变速率提高一个数量级。置氢Ti-6Al-4V合金变形激活能随置氢量增加呈下降趋势,变形由不受扩散机制控制转变为受扩散机制控制。Hot deformation of hydrogenated Ti-6Al-4V alloy has been carried out with the Hot-simulator of Gleeble-1500D. The microstructures of hydrogenated alloys have been investigated by XRD and OM. Activation energies of the alloys with different hydrogen content have been calculated. The results show that with the increase in hydrogen content, the fraction of β phase increases and the flow stress at high temperature decreases obviously, whose change presents a sunken curve, i.e. after reaching a minimum then increases at a particular processing temperature. The hydrogen content corresponds to the minimum in stress decreases when the temperature is increased. The deformation temperature can decrease 50 ℃ or strain rate enhance a order of magnitude in proper hydrogenated at a constant stress. The activation energy decreases with the increase of hydrogen content, and different deformation mechanisms are exhibited.

关 键 词：TI-6AL-4V合金 置氢 高温塑性变形 

分 类 号：TG146.23[一般工业技术—材料科学与工程]