中国有色金属学报(英文版)
中國有色金屬學報(英文版)
중국유색금속학보(영문판)
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
2014年
12期
3804-3809
,共6页
徐泓鹭%苏小明%袁广银%金朝晖
徐泓鷺%囌小明%袁廣銀%金朝暉
서홍로%소소명%원엄은%금조휘
镁%原子模拟%变形孪晶%孪晶界迁移%位错-晶界相互作用
鎂%原子模擬%變形孿晶%孿晶界遷移%位錯-晶界相互作用
미%원자모의%변형련정%련정계천이%위착-정계상호작용
magnesium%atomistic simulation%deformation twinning%twin boundary migration%dislocation-grain boundary interaction
通过分子动力学模拟(MD),研究在HCP镁中的一个对称倾斜晶界与基面滑移的位错相互作用而激发的变形孪晶,也就是孪晶形核与长大的过程(或者是孪晶界迁移,TBM)。{1121}孪晶在该过程中是最易被激发的孪生模式。一旦这样的孪晶形成了,它们就会不断长大。该种孪晶界迁移是由单纯的原子位置局域调整造成的。在模拟过程中同时也产生了二次孪晶{1122}。该二次孪晶模型的孪晶形核与长大需要克服的能垒与{1121}孪晶不同。同时,二次孪晶的孪晶界迁移过程是通过孪晶界上的锥形滑移而激发的。
通過分子動力學模擬(MD),研究在HCP鎂中的一箇對稱傾斜晶界與基麵滑移的位錯相互作用而激髮的變形孿晶,也就是孿晶形覈與長大的過程(或者是孿晶界遷移,TBM)。{1121}孿晶在該過程中是最易被激髮的孿生模式。一旦這樣的孿晶形成瞭,它們就會不斷長大。該種孿晶界遷移是由單純的原子位置跼域調整造成的。在模擬過程中同時也產生瞭二次孿晶{1122}。該二次孿晶模型的孿晶形覈與長大需要剋服的能壘與{1121}孿晶不同。同時,二次孿晶的孿晶界遷移過程是通過孿晶界上的錐形滑移而激髮的。
통과분자동역학모의(MD),연구재HCP미중적일개대칭경사정계여기면활이적위착상호작용이격발적변형련정,야취시련정형핵여장대적과정(혹자시련정계천이,TBM)。{1121}련정재해과정중시최역피격발적련생모식。일단저양적련정형성료,타문취회불단장대。해충련정계천이시유단순적원자위치국역조정조성적。재모의과정중동시야산생료이차련정{1122}。해이차련정모형적련정형핵여장대수요극복적능루여{1121}련정불동。동시,이차련정적련정계천이과정시통과련정계상적추형활이이격발적。
Deformation twinning, i.e., twin nucleation and twin growth (or twin boundary migration, TBM) activated by impinged basal slip at a symmetrical tilt grain boundary in HCP Mg, was examined with molecular dynamics (MD) simulations. The results show that the {1 1 21}-type twinning acts as the most preferential mode of twinning. Once such twins are formed, they are almost ready to grow. The TBM of such twins is led by pure atomic shuffling events. A secondary mode of twinning can also occur in our simulations. The {1122} twinning is observed at 10 K as the secondary twin. This secondary mode of twinning shows different energy barriers for nucleation as well as for growth compared with the {1 1 21}-type twining. In particular, TBMs in this case is triggered intrinsically by pyramidal slip at its twin boundary.