鋁合金輪圈鑄造模擬分析

ANALYSIS OF CASTING PROCESS OF ALUMINUM WHEEL

余家杰(Chia-Chieh Yu)

指導教授 ： 徐業良

元智大學/工程學院/機械工程學系/碩士(2003年)

摘要

汽車用鋁合金輪圈通常以重力鑄造，鑄造過程中如果冷卻參數和模具初始溫度沒有妥善控制，凝固之後常會造成輪圈內部縮孔，造成輪圈洩氣。
本研究利用電腦輔助分析軟體，模擬在鋁合金輪圈鑄造程序，以穩態收斂之分析結果，依液體陷入(liquid entrapped)現象發展一縮孔指標(Shrinkage Index, SI)，並觀察吹水、吹氣、模具初始溫度、以及輪圈幾何造型對於輪圈鑄造縮孔指標之影響，最後並找出SI數值與實際測試中輪圈壓洩測試率之關係。未來應可以此模擬程序與縮孔指標預測輪圈鑄造品質，找出最佳製程參數以期降低輪圈壓洩漏氣率，提高輪圈鑄造品質，降低輪圈生產成本。

關鍵字

電腦輔助工程分析 ； 鋁合金輪圈 ； 縮孔指標 ； 輪圈洩氣率

並列摘要

Aluminum disc wheels intended for normal use on passenger cars are commonly produced by gravity casting. If the cooling process and initial temperature of mold are not well controlled, shrinkage cavity will occur after solidification, which might cause leakage problems to the disc wheel.
This thesis simulated the casting process by computer simulation, and a Shrinkage Index (SI) is defined using the phenomenon of liquid entrapped. This thesis then discussed the influence of cooling process, initial temperature, and geometry of the wheel on SI after the mold temperature has converged. The relationship between SI and the percentage of wheels that have leakage in real test was discussed. We can use the simulation process and SI to predict the quality of the casting wheel and to find the optimal parameters.

並列關鍵字

Aluminum disc wheels ； shrinkage ； leakage ； computer simulation ； Shrinkage Index

參考文獻

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