鐵顆粒添加對鎂鋅鈣非晶質合金熱性質及機械性質影響之研究

The Influence of Iron-particles Addition on Thermal and Mechanical Properties of Mg-based Amorphous Alloy

吳哲瑋(Che-Wei Wu)

指導教授 ： 鄭憲清

國立中央大學/工學院/材料科學與工程研究所/碩士(2014年)

摘要

近年來，生物可降解材料在醫學界備受矚目，原因是其能夠在生物體內自行分解，不需藉由二次手術取出，有效降低術後感染的風險。鎂、鋅、鈣為人體內含量極高之金屬元素，形成非晶質合金後，不但具有良好的生物相容性，同時具有和骨骼相近之楊氏係數，在骨科駐植物的應用上相當具有潛力。然而，鎂鋅鈣非晶質合金在常溫下呈現出嚴重脆性，因此實際應用上仍有困難尚待克服。本實驗首先針對MgxZn95-xCa5 (x = 65-67)合金系統進行最佳玻璃形成能力探討，發現Mg66Zn29Ca5具有相對較佳的玻璃形成能力，接著利用Mg66Zn29Ca5為基材，添加等軸鐵顆粒製作出非晶質合金複材。實驗結果顯示，鐵顆粒具有良好的散佈強化效果，可有效提升其壓縮破裂強度，基材抗壓強度由394 MPa提升至650 MPa，但由於鐵顆粒與基材介面契合度不佳緣故，塑性變形量並無明顯提升。

關鍵字

生物降解 ； 生物相容性 ； 非晶質合金 ； 骨科駐植物 ； 裂紋

並列摘要

The biodegradable materials can be dissolved spontaneously in human body, hence the secondary surgery is not required and many infections can be avoided. Therefore, biodegradable materials have attracted great attention in the field of medical research. Magnesium, Zinc and Calcium are elements with high content in human body. The Mg-Zn-Ca amorphous alloy has become a potential candidate of orthopedic implants due to its high bio-compatibility and low Young’s Modulus that is quite close to human bones. However, it still has many restrictions on applications because of its inherit brittleness. The glass forming ability (GFA) of MgxZn95-xCa5 (x = 65-67) alloying system was evaluated in the beginning of this study, and the result reveals that the Mg66Zn29Ca5 has the highest value of GFA in this alloy system. Therefore, the composition of Mg66Zn29Ca5 was utilized as the matrix to fabricate Mg-based BMGC with equiaxial iron particles addition. The result of compression test also shows the dispersion strengthening effect of the iron particles on increasing the fracture strength of the Mg-based BMG. The fracture strength of Mg66Zn29Ca5-based BMGC can be increased from 394 MPa to 650 MPa. However, no obvious improvement of plasticity can be obtained for this Mg-based BMGC due to the bad adhesion between the iron particles and the amorphous matrix.

並列關鍵字

biodegradable ； biocompatibility ； orthopedic implants ； bulk metallic glass composites (BMGCs) ； crack

參考文獻

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