(合肥工業(yè)大學 材料科學與工程學院，合肥 230009)
摘 要: 本文研究了Al-20Si-xCu系列合金的凝固過程和熱裂行為。采用差熱分析法(DTA)對凝固過程進行了分析，用自制的T形模具對其熱裂行為進行了研究，并用Clyne和Davis模型對三元合金熱裂敏感性進行了預測。結果表明：用裂紋敏感性系數(CSC)預測的合金熱裂敏感性趨勢與Al-20Si-xCu系列合金的實驗結果一致，合金的熱裂敏感性(Hot tearing sensitivity，HTS)大小順序為Al-20Si-3Cu＞Al-20Si-4Cu＞Al-20Si-2Cu＞Al-20Si-1Cu。同時，運用ProCAST模擬軟件采用基于有限元(FEM)的數值計算和綜合求解的方法，對合金鑄件充型、凝固和冷卻過程進行模擬，預測合金澆注過程產生的熱裂應力以及熱裂指標(HTI)等參數，其數值模擬結果與實驗結果吻合較好。
關鍵字: 鋁硅合金；熱裂敏感性；熱分析；數值模擬
（School of Materials Science and Engineering, Hefei University of Technology, Hefei 230009, China）
Abstract:The solidification process and hot tearing behavior of Al-20Si-xCu series alloys were investigated. The solidification process was analyzed by differential thermal analysis (DTA) and the hot tearing behavior was studied by self-made “T” mold, the Clyne and Davis models were used to predict the hot tearing sensitivity of ternary alloy. The results show that the hot tearing sensitivity predicted by the crack sensitivity coefficient (CSC) is consistent with the experimental results of Al-20Si-xCu series alloys. The hot tearing sensitivity (HTS) of the alloys is Al-20Si-3Cu＞Al-20Si-4Cu＞Al-20Si-2Cu＞Al-20Si-1Cu. At the same time, ProCAST simulation software was used to simulate the filling, solidification and cooling processes of alloy castings by using the method of numerical calculation and comprehensive solution based on finite element method (FEM), and the hot tearing stress and hot tearing index (HTI) were predicted. The numerical simulation results were in good agreement with the experimental results.
Key words: aluminum-silicon alloy; hot crack sensitivity; thermal analysis; the numerical simulation
