本研究主要目的在量測半固態鎂合金在壓鑄過程中，鑄件與模具間的界面熱傳導係數(h)。最初利用CA-CCA法 ( Computer Aided- Cooling Curve Analysis)來求得固相率對溫度的關係，並將此數據代入Inverse Method中處理潛熱釋放的模式。並依照所求得的固相率溫度，在適合半固態壓鑄的固相率下進行半固態鎂合金界面熱傳導係數的量測，來求得一系列h-T的數據。
　　本實驗為符合J.V. Beck提出的Inverse Method理論，發展出一維熱傳密閉式的模具，來提供鎂合金等活性大的金屬或合金做界面熱傳導係數的量測。將量測所得T-t的數值代入Inverse Method程式中計算，得到h-T的關係，藉由圖表分析鑄件與模具間在降溫過程中的熱傳行為。
　　本研究首先以CA-CCA的方式計算求出鎂合金固相率對溫度的關係，再根據此數據所提供的固相率溫度進行半固態鎂合金界面熱傳導係數的量測。在界面熱傳導係數量測方面，液態AZ91D鎂合金凝固過程中，h值在1600~2900 W/m2•℃之間，經歷五個階段的轉折變化；而固相率30%的AZ91D鎂合金，其h值在最初下降過程中，有與純液態AZ91D第三階段相似的熱傳行為，之後保持穩定平緩下降的趨勢，其值約在1300~1500 W/m2•℃之間；而隨著固相率的增加，半固態AZ91D的h值則些微降低，固相率50% AZ91D鎂合金的h值比30% AZ91D鎂合金低約100 W/m2•℃左右。
　　本研究歸納出半固態鎂合金的界面熱傳行為主要受到半固態形態的影響，所以在h值上無太大的轉折變化；且固相率越低，與模具的接觸效果越好，h值也較高。

　　The main object of this research is to measure the interfacial heat transfer coefficient (h) between semi-solid magnesium alloy and mold during die casting process. In the beginning，CA-CCA method is used to obtain the relationship between solid fraction and temperature，and then，these data are taken into Inverse Method program to deal with mode of releasing latent heat. The experiment of measurement of interfacial heat transfer coefficient is done under suitable solid fraction which is usually taken in semi-solid process to obtain series of h-T data.
　　In order to accord with Inverse Method proposed by J.V. Beck，this experiment develops the mold with one-dimensional airtight system to offer the measurement of interfacial heat transfer coefficient in big activation metal such as magnesium alloy. After calculating the Inverse Method program with measured T-t values and receiving h-T relations，the h-T diagrams are analyzed to describe the behavior between casting and mold.
　　First，CA-CCA method is used to calculate the relationship between solid fraction and temperature. According to these data，temperature of semi-solid magnesium alloy is taken in the measurement of interfacial heat transfer coefficient. In the measurement of interfacial heat transfer coefficient，the h values of liquid AZ91D are in the range between 1600~2900 W/m2•℃ and experience five stages. And the behavior of the h values of AZ91D with 30% solid fraction is similar to the third stage of h-T curve of liquid AZ91D in the beginning of falling down，and then， go downward steadily with the values between 1300~1500 W/m2•℃. With increasing in solid fraction，the h values of semi-solid magnesium alloy are lower；the h values of AZ91D with 30% solid fraction are 100 W/m2•℃ lower than that with 50% solid fraction.
It is concluded that because of the effect of semi-solid magnesium alloy morphology，there is not so much change in h values；and the lower solid fraction，the higher h value.

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