Deformation behaviour of nanocrystalline magnesium
Deformation behaviour of nanocrystalline magnesium
复制标题
纳米晶镁的变形行为
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
P. McCormick
中科院分区：
文献类型：
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作者：
S. Hwang;P. McCormick
研究了纳米晶镁的变形行为。在干燥惰性气体气氛中采用高能球磨法制备纳米晶镁粉，真空冷压成型为致密的圆柱形试样。在室温下进行压缩试验。样品表现出显着的高值的延展性，并在烧结试样的屈服强度显着改善。烧结试样的应力-应变曲线上观察到较大的屈服下降。还测量了流变应力的应变速率敏感性，并与市售纯镁棒的值进行了比较。活化体积以及应力指数的值被发现是显着较低的纳米晶样品。这是推测晶界滑动控制在纳米晶镁样品的变形机制。
The deformation behaviour of nanocrystalline magnesium was studied. Nanocrystalline magnesium powder was prepared by high energy ball milling in a dry inert gas atmosphere and vacuum cold pressed to form fully dense cylindrical specimens. Compression tests were carded out at room temperature. The samples exhibited remarkably high values of ductility, and a significant improvement in yield strength in sintered specimens. Large yield drops were observed on the stress-strain curve of sintered specimens. The strain rate sensitivity of the flow stress was also measured and compared to the values for commercially available pure magnesium bars. The values of activation volume as well as the stress exponent were found to be significantly lower in the nanocrystalline samples. It is speculated that grain boundary sliding controls the deformation mechanism in the nanocrystalline magnesium samples.