摘要
采用动态机械热分析(DMA)技术研究了Ca/Y变质处理对Mg-0.6Zr合金阻尼行为的影响,分析了合金随应变振幅和温度阻尼变化的机制。结果表明,添加0.3%Ca和0.3%Ca+0.1%Y(质量分数,下同)变质处理后的细晶强化和固溶强化作用提高了合金的拉伸强度和延伸率,同时由于Ca/Y元素的加入及晶界数量增多对位错运动的进一步阻碍作用降低了合金的应变振幅效应,从而降低了其阻尼性能;研究还发现Mg-0.6Zr合金在温度为75℃处出现一个明显的阻尼峰,而添加0.3%Ca+0.1%Y变质处理后,并未出现阻尼峰。分析认为,试验合金的阻尼机制可按G-L位错钉扎模型和晶界面软化及粘性滑动机制解释。
The effect of Ca/Y modification on damping behavior of Mg-0.6Zr alloy are investigated by dynamic mechanical analyzer and the damping mechanism depended on strain amplitude and temperature is al- so analyzed. The results showed the alloy tensile strength and elongation is improved by fine-grain intensification and solid solution intensification upon modification with the addition of Ca/Y 0.3 %Ca,0.3%Ca＋0.1%Y（mass %）. Meanwhile,the addition of Ca/Y and further impediment of the dislocation movement due to more grain boundary has reduced alloy strain amplitude effect,resulting in lower damping performance. It is also found out that distinct damping peak（P1 ）appears in Mg-0.6Zr alloy at 75 ℃ while the modi- fication with the addition of 0.3 %Ca＋0.1%Y suspends the damping peak. The damping mechanism of the tested alloys could be explained as mechanism of G-L dislocation damping model and viscous sliding and softening of the grain boundaries.
出处
《稀有金属与硬质合金》
CAS
CSCD
2007年第3期23-27,53,共6页
Rare Metals and Cemented Carbides
