組織與性能的影響
(1. 沈陽(yáng)工業(yè)大學(xué) 材料學(xué)院，沈陽(yáng) 110023；
2. 沈陽(yáng)航空工業(yè)學(xué)院 材料系，沈陽(yáng) 110034)
摘 要: 對(duì)固溶處理過(guò)程中鑄造Al-Si-Cu-Mg合金析出相溶解過(guò)程進(jìn)行了研究。結(jié)果表明：在固溶處理初期，組織中θ相的數(shù)量逐漸減少，但在(FeMn)3SiAl12相中還有一定的Cu含量；而固溶后期，富鐵相中的Cu含量也明顯降低，且難溶的Al3Ti針狀相也發(fā)生鈍化，但部分Q相尚存在；隨著固溶時(shí)間的延長(zhǎng)，合金基體中Cu和Mg的含量逐漸增多，且富Mn和富Ti相也在合金基體中略有溶解；合金的固溶強(qiáng)化作用主要來(lái)源于富Cu相的溶解。在Al-Si-Cu-Mg固溶處理過(guò)程中，合金力學(xué)性能的提高主要來(lái)源于共晶硅相形貌的改善、析出相溶解引起的固溶強(qiáng)化及組織的均勻化。
關(guān)鍵字: 鑄造Al-Si-Cu-Mg合金; 熱處理; 析出相; 溶解; 固溶強(qiáng)化
and properties of Al-Si-Cu-Mg cast alloys
（1. School of Materials Science and Engineering,Shenyang University of Technology, Shenyang 110023, China;
2. Department of Material, Shenyang Institute of Aeronautical Engineering, Shenyang 110034, China）
Abstract:The dissolution of the intermetallic phases was studied and the function of solution strengthening in Al-Si-Cu-Mg casting alloys during solution heat treatment was analyzed. The results show that the θ phase (Al2Cu) dissolves gradually in the initial stage of solution, but still exists around (FeMn)3SiAl12 particles until holding time prolongs. In the final stage of solution the needle-like Al3Ti phases blunt but Q phases (Cu2Mg8Si5Al4) still exist. With the solution time prolonging, the amounts of Cu and Mg atoms in matrix increase, and Mn and Ti intermetallics dissolve partly. However, the function of solution strengthening mainly originates from Cu atoms. The increase of mechanical properties of alloy during solution heat treatment are due to the combined effect of dissolution of the intermetallic phases, uniformity of structure and spheroidization of silicon particles.
Key words: Al-Si-Cu-Mg cast alloy; heat treatment; intermetallic phases; dissolution; solution strengthening
