CSIR-National Metallurgical Laboratory , Jamshedpur 831007 , India.
Department of Chemical Engineering , IIT Delhi , New Delhi 110 016 , India.
J Phys Chem B. 2019 Oct 31;123(43):9238-9249. doi: 10.1021/acs.jpcb.9b00139. Epub 2019 Oct 23.
Molecular dynamics simulation is used to investigate the mechanical properties of the semiflexible polymer during multiaxial tensile deformations. The multiaxial tensile deformations can be imposed in totally or partially constrained modes. These types of deformations may be observed during the sudden deformation of polymeric material in the areas of aerospace, automobile, defense applications, etc. It is found that the constrained multiaxial deformation leads to the formation of nanovoids into the polymer sample. The high Young's modulus and yield strength for the totally constrained modes of tensile deformation are due to the energy required to create voids. The variation in von Misses stress, void volume, and bond order parameter with strain indicates the occurrence of brittle fracture during totally constrained tensile deformations. The partially constrained tensile deformations lead to the improvement in bond order parameter and lesser creation of nanovoids within the system. The system shows the characteristic strain hardening before failures.
分子动力学模拟被用于研究多轴拉伸变形过程中半刚性聚合物的力学性能。多轴拉伸变形可以采用完全或部分约束模式施加。在航空航天、汽车、国防应用等领域，聚合物材料的突然变形可能会观察到这些类型的变形。研究发现，约束多轴变形会导致聚合物样品中形成纳米空穴。完全约束拉伸变形模式的高杨氏模量和屈服强度是由于形成空穴所需的能量。随着应变的变化，von Misses 应力、空穴体积和键序参数的变化表明在完全约束拉伸变形过程中发生了脆性断裂。部分约束拉伸变形会导致键序参数的提高和系统中空纳米穴的生成减少。该系统在失效前表现出特征应变硬化。
