钨丝的回复和再结晶形核机制研究

来源期刊：中南大学学报(自然科学版)1990年第4期

论文作者：刘心宇 左铁镛

文章页码：414 - 419

关键词：再结晶(冶金)； 回复； 形核

Key words：recrystallization(metallurgy)； recovery； nucleation

摘    要：采用扫描电镜、透射电镜系统地研究了在1000～2400K温度范围内退火的dia.0.43mm的纯钨和掺杂钨丝的显微组织变化。研究结果表明,这两种钨丝在退火过程中所出现的纤维宽化现象主要是由于平面亚纤维边界离解、亚纤维聚合所至。这种纤维宽化并非为一次再结晶或原位再结晶,而是加工态钨丝回复过程中的一个特殊阶段。纯钨和掺杂钨丝主要都是通过宽化纤维中的粗大亚晶空间胞壁离解、粗大亚晶的二次聚合而形核。但是由于钾泡对于位错和晶界运动的钉扎作用,掺杂钨丝的纤维宽化和形核过程严重受阻,其回复和再结晶过程缓慢、同步发生并延缓到2000K高温。

Abstract: The microstructures of annealed pure and doped W wires of 0.43 mm diameter were investigatedby TEM and SEM.The results indicate that fiber widening in annealing of W wires is mainlycaused by separating of subfiber boundaries and coalescing of subfibers.Fiber widening is not aprimary recrystallizion or a recrystallization in situ but a special stage in recovery of deformed Wwire.Both pure and doped W wires nucleate through secondary coalescence of large subgrains inwidened fibers.But because of the pinning of K-filled bubbles on the dislocations and grainboundaries,the fiber coalescence and nucleation of doped W wire are retarded seriously,recoveryand recrystallization developed slowly and synchronistically,and they are prolonged to the tem-perature of 2000K.