礦石鑄件與鑄鐵相比具有低密度、高阻尼、動剛性佳等特性，且易於室溫下製作組裝，近年來常用於精密機台及量測儀器之主要結構及精密部件；但因其為複合材料，對於材料組成對其機械性質如彈性模數及阻尼比等則尚未建立一套系統性預測模型，故本文欲建立以四種粒徑組合礦石為變數之機械性質與阻尼比預測模型。
本文首先對礦石及樹脂進行奈米壓痕測試以獲得鑄件組成原料之彈性模數。以田口法設計四種粒徑群組成之試體並進行敲擊、彎曲及壓縮測試以獲得彈性模數、阻尼比、動態彈性模數、抗壓及抗彎強度；以田口法分析數據以獲得各粒徑礦石對彈性模數、阻尼比、抗壓強度、抗彎強度之影響。透過基因編程建立各粒徑群礦石對彈性模數、阻尼比、動態彈性模數、抗壓強度、抗彎強度之預測模型並與複合材料彈性模數預測模型比較準確度，最後以基因演算法獲得最大化上述性質之配比與預測值。
實驗結果發現，於本文組合範圍內，礦石鑄件之阻尼比較鑄鐵高8~13倍。將抗壓及抗彎強度結果與配比組合及礦石破斷面比較可發現強度與最大粒徑礦石成正向關係，此與田口分析結果相呼應；田口分析也顯示，最大粒徑礦石含量對阻尼比、抗壓強度及抗彎強度有顯著的影響，最小粒徑礦石含量對彈性模數有最大的貢獻度；經驗證本模型及複合材料彈性模數預測模型皆具有良好的準確性。

Mineral cast is often used as the main structures and components of measuring instruments and precision machines. Compared with cast iron, mineral cast has better characteristics of lower density, higher damping ratio and dynamic stiffness, etc. Moreover, mineral cast is easily to be made and assembled at room temperature. However, it is difficult to establish an analytical prediction model for mechanical properties and damping ratio of composite materials. Therefore, a prediction model for mechanical properties and damping ratio by considering four particle sizes as variables is proposed in this paper. First, elastic modules of epoxy and four kinds of particle composition mineral were obtained by nano indentation. Then, the Taguchi method is utilized to design mixtures and analyze the contributions of each particle size to elastic modulus, damping ratio, dynamic elastic modulus, compressive strength and flexural strength. Genetic programming was applied to establish the prediction model with four factors of different particle sizes. Finally, genetic algorithm is used to obtain the prediction values of maximum mechanical properties, damping ratio and mixing proportion of four particle sizes. The results of this study show that, within the range of experimental setting, damping ratio of mineral cast is 8~13 times higher than cast iron. By comparing the compressive strength, flexural strength, mixing proportion and fracture surface of specimens, maximum strength is proportional to the volume ratio of the biggest mineral, which is in agreement with the results of Taguchi analysis. Taguchi analysis also shows that the ratio of the biggest mineral has a significant effect on damping ratio, compressive strength and flexural strength. Moreover, the results also shows that the ratio of the smallest mineral has the greatest contribution to elastic modulus. This paper provides the process to establish a prediction model of target properties under different conditions and predicts the maximum value of target properties and ratio of different compositions.

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