(西北工業(yè)大學(xué) 凝固技術(shù)國家重點實驗室,西安 710072)
摘 要: 采用微觀相場法研究鋁基合金中界面錯配應(yīng)力對沉淀相粗化過程的影響。結(jié)果表明:界面錯配應(yīng)力為零時,粗化機制符合經(jīng)典LSW機制;錯配應(yīng)力較大時,粗化機制是位向控制粗化機制,沉淀相顆粒沿彈性“軟”方向規(guī)則分布;中等界面錯配應(yīng)力時,粗化機制為兼具位向控制和LSW機制的混合機制;界面錯配應(yīng)力促進沉淀相延彈性軟方向生長;沉淀相的粗化過程和長大過程交疊進行。
關(guān)鍵字: 鋁合金;粗化機制;粗化速率;界面錯配應(yīng)力
(State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072, China)
Abstract:Influence of interface mismatch stress on precipitate coarsening process in aluminum alloys was investigated using a microscopic phase-field model. The results show that, when the interface mismatch stress is zero, the coarsening mechanism complies with the classic LSW theory. When the mismatch stress is large, the coarsening mechanism is orientation-controlled. The precipitate particles are distributed periodically along the elastic soft directions. At medium interface mismatch stress, the coarsening mechanism is mixed with both orientation-control and LSW mechanism. The interface mismatch stress promotes precipitate growing in elastic soft directions. The coarsening process and growth process of the precipitates overlap with each other in proceeding.
Key words: aluminum alloy; coarsening mechanism; coarsening rate; interfacial mismatch stress


