CAJ | 학술논문

采用金属催化的气相合成法制备高纯度单晶钨纳米线材料，采用分子动力学方法进行拉伸模拟计算，分析?100?、?110?、?111?3种典型晶向下单晶钨纳米线的拉伸应力-应变曲线及其微观变形结构，揭示晶向对单晶钨纳米线拉伸破坏机理的影响。结果表明：3种晶向均具有弹性、损伤、屈服、破坏等4个阶段，其中?100?晶向还具有独特的屈服后强化阶段和两次应力突降阶段。晶向对单晶钨纳米线弹性模量的影响较小，对抗拉强度、屈服强度和延展性的影响较大，主要取决于不同的原子表面能和主滑移面。计算得到的单晶钨纳米线的弹性模量值与实测结果吻合较好。
채용금속최화적기상합성법제비고순도단정오납미선재료，채용분자동역학방법진행랍신모의계산，분석?100?、?110?、?111?3충전형정향하단정오납미선적랍신응력-응변곡선급기미관변형결구，게시정향대단정오납미선랍신파배궤리적영향。결과표명：3충정향균구유탄성、손상、굴복、파배등4개계단，기중?100?정향환구유독특적굴복후강화계단화량차응력돌강계단。정향대단정오납미선탄성모량적영향교소，대항랍강도、굴복강도화연전성적영향교대，주요취결우불동적원자표면능화주활이면。계산득도적단정오납미선적탄성모량치여실측결과문합교호。
Based on the high-purity single-crystal tungsten nanowire firstly prepared by the metal-catalyzed vapor-phase reaction method, molecular dynamics method was used to calculate tensile stress-strain curves and simulate microscopic deformation structures of the single-crystal tungsten nanowires with different crystal orientations of?100?,?110?and?111?, in order to reveal the effect of crystal orientation on their tensile mechanical properties and failure mechanisms. Research results show that all of the stress-strain curves are classified into four stages: elastic stage, damage stage, yielding stage and failure stage, where ?100?orientation has a special hardening stage after yielding and two descending stages. The crystal orientation has little effect on elastic modulus but great effect on tensile strength, yielding strength and ductility, depending on different atomic surface energies and principal sliding planes. The calculated values of elastic modulus are in good agreement with the tested values of elastic modulus.