論文
金属のねじり変形に及ぼす圧縮静水圧応力の影響
—分子動力学による解析—
キーワード:
hydrostatic pressure,
molecular dynamics,
torsional deformation,
pure aluminum,
mechanical properties
2016 年 82 巻 5 号 p. 448-453
詳細
2016 年 82 巻 5 号 p. 448-453
It is known that the mechanical properties of metals change with the given compressive hydrostatic pressure. However, the mechanism of such phenomenon has not been fully understood, because most experiments have been carried out using polycrystalline materials. In this study, in order to clarify such a mechanism at an atomic-scale, a molecular dynamics simulation of the torsion process on a monocrystalline aluminum was performed under relatively high compressive hydrostatic stresses. In the simulation, influences of the pore defect on mechanical properties and deformation of the workpiece were also examined. As a result, it was confirmed that both the modulus of rigidity and yield shear stress were increased and the generation of dislocations was decreased with increasing the compressive hydrostatic stress irrespective of the presence of defect. However, the increase in the yield shear strain was only observed for the workpiece with a pore defect, and this trend was discussed and verified by using a simple fracture mechanics model.
