CAJ | 학술논문

【目的】研究初始原子对亚晶界湮没机制的影响。【方法】采用晶体相场模型模拟亚晶界结构在应力作用下的湮没过程，并从位错运动和能量变化角度对湮没过程进行分析，同时讨论初始原子在两晶粒交界处的对齐程度对其后亚晶界湮没的影响。【结果】研究表明，初始晶界原子排列错位1/4晶格常数时，首先位错在晶界处攀移，然后位错同时分离成两个，一个分离出的位错停留于原位，另一个则进入亚晶内部进行攀移和滑移直至相遇湮没，之后原来停留于原位的位错在攀移一段时间后也进入亚晶内部进行攀移和滑移，最终相遇湮没，形成单晶。而初始晶界原子排列错位1/2晶格常数时，湮没过程与初始晶界原子排列错位1/4晶格常数时的情况存在很大的差异。【结论】亚晶界湮没过程中，位错直接进入亚晶内部进行攀移和滑移，位错间发生复杂的相互作用，最终位错全部湮没，形成单晶。同时体系能量将随应力的增加而波动下降，形成4个明显的峰谷。
【목적】연구초시원자대아정계인몰궤제적영향。【방법】채용정체상장모형모의아정계결구재응력작용하적인몰과정，병종위착운동화능량변화각도대인몰과정진행분석，동시토론초시원자재량정립교계처적대제정도대기후아정계인몰적영향。【결과】연구표명，초시정계원자배렬착위1/4정격상수시，수선위착재정계처반이，연후위착동시분리성량개，일개분리출적위착정류우원위，령일개칙진입아정내부진행반이화활이직지상우인몰，지후원래정류우원위적위착재반이일단시간후야진입아정내부진행반이화활이，최종상우인몰，형성단정。이초시정계원자배렬착위1/2정격상수시，인몰과정여초시정계원자배렬착위1/4정격상수시적정황존재흔대적차이。【결론】아정계인몰과정중，위착직접진입아정내부진행반이화활이，위착간발생복잡적상호작용，최종위착전부인몰，형성단정。동시체계능량장수응력적증가이파동하강，형성4개명현적봉곡。
Objective]The aim of this study is researching the influence of initial atomic arrange-ment to sub-grain boundary annihilation.[Methods]The phase field crystal model is employed to simulate the annihilation process of sub-grain boundary (SGB)under strain.We have ana-lyzed the process from two aspects of dislocation movement and system energy,then discussed the influence of initial atomic arrangement on the subgrain annihilation.[Results]The simula-tion result show that,as the lattice misfit is a/4(a:The distance between atoms),dislocations firstly climb along the SGB under strain,then all dislocations break up into two new dislocations. One of the two dislocations climb and glide into the grain.For a while,the dislocation crosses the grain until it is annihilated with another disloca-tion moving along opposite direction.At this moment,the other continues to move in the style of climbing.When getting enough energy,they climb and glide into the grain,too.Finally,they are annihilated with another dislocation and the two grain systems with SGB become one grain system.As the lattice misfit is a/2,the annihilation process changes largely compared with that of lattice misfit being a/4.[Conclusion]Although all dislocations climb and glide into the grain at the beginning of the simulation,a complex interaction appear during the process,finally all dislocation are annihilated and the two grain systems with SGB become one grain system.The system energy of the process decreases with strain increasing,and 4 peaks and valleys appear during this process.