Abstract: The void growth process and microscopic mechanical properties of a single crystal α-Ti cube containing a spherical void in uniaxial tension loading were investigated by molecular dynamics simulation. The results showed that the stress-strain curves of the material appeared four different stages at the low strain rate: the initial linear stage, the sharp drop stage, the rapid increase stage and the rapid drop to the steady stage. Microstructure observation from MD results also indicated that the pyramidal〈a〉slip system{1101}〈1120〉 and {1011}twinning near the equator area of the void was the main form of void growth. The effects of specimen size, strain rate, void volume fraction on mechanical properties of single crystal α-Ti materials were studied, the result showed that the initial yield stress of the materials decreased with the increase both in specimen size and void volume fraction, but increased with the increase in strain rate; the Young’s modulus of the material depended only on the void volume fraction which decreased with the increase of the void volume fraction.
丁军, 汪建, 黄霞, 王路生, 赵昊男, 宋鹍. 含孔洞缺陷的单晶α-Ti单轴拉伸下的微观变形机理及力学性能[J]. 材料导报, 2018, 32(18): 3171-3180.
DING Jun, WANG Jian, HUANG Xia, WANG Lusheng, ZHAO Haonan, SONG Kun. Micro Deformation Mechanism for the Void Defects Embedded in a Single Crystal α-Ti in Tension and Its Effect on Mechanical Properties. Materials Reports, 2018, 32(18): 3171-3180.
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