銅-鈦基塊狀非晶合金之粉末冶金製程研究

Formation of Cu-Ti-based Bulk Amorphous Alloys by Powder Metallurgy Route

賴永祥(Yong-Siang Lai)

指導教授 ： 胡家榮

大同大學/工程學院/材料工程學系所/碩士(2008年)

摘要

本研究主要利用機械合金法(Mechanical Alloying)合成銅-鈦基(Cu-Ti based)合金粉末之非晶質化行為，並以真空熱壓法及擠壓成型製備塊狀非晶合金。升溫速率5℃/min之DSC熱分析下，幾種非晶質粉末在結晶反應發生前發現有寬廣過冷液態區△Tx的存在，合金Cu40Ti40Ni15Sn5為114K、合金Cu40Ti40Ni15Si5為59K、合金Cu50Ti40Sn5B5為78K、合金Cu50Ti40Ni5B5為88K。以真空熱壓法及擠壓成型製備Cu40Ti40Ni15Sn5、Cu40Ti40Ni15Si5、Cu50Ti40Sn5B5、Cu50Ti40Ni5B5塊狀非晶合金，塊材孔洞的生成與擠壓成型失敗為氧化所導致。塊材硬度值分別Cu40Ti40Ni15Sn5為658.6HV；Cu40Ti40Ni15Si5為624.5HV；Cu50Ti40Sn5B5為617.6HV；Cu50Ti40Ni5B5為604.5HV。磨耗試驗得知塊材硬度值越大其磨耗下重量損失越小，抗磨耗效果較佳。耐腐蝕試驗得知，非晶質合金Cu40Ti40Ni15Sn5、Cu40Ti40Ni15Si5，有較優異的抗腐蝕特性。且發現於NaCl水溶液的氧化反應之後都有些微的鈍化區形成，但其鈍化區的電位分佈並不大。

關鍵字

機械合金法 ； 銅基非晶質合金 ； 過冷液態區 ； 真空熱壓法 ； 擠壓成型法 ； 磨耗試驗 ； 極化試驗

並列摘要

This study examined the amorphization behavior of Cu-Ti based alloy powders synthesized by mechanical alloying technique and investigation of consolidation by vacuum hot pressing and vacuum hot extrusion. The phase stabilities of as-milled powders were studied by DSC measurement at 5K/min heating rate. The amorphous powders were found to exhibit a wide supercooled liquid region before crystallization.
The temperature interval of the supercooled liquid region (ΔTx) is 114K for Cu40Ti40Ni15Sn5, 59K for Cu40Ti40Ni15Si5, 78K for Cu50Ti40Sn5B5, 88K for Cu50Ti40Ni5B5 respectively. Surface oxidation of powders in milling and consolidation processes led to larger amount of porosity and extruding failure. In addition, the hardness of the bulk amorphous alloys is 658.6HV for Cu40Ti40Ni15Sn5, 624.5HV for Cu40Ti40Ni15Si5, 617.6HV for Cu50Ti40Sn5B5, and 604.5HV for Cu50Ti40Ni5B5. It leads to better wear resistance for less weight loss as hardness increasing. Furthermore, Cu40Ti40Ni15Sn5 and Cu40Ti40Ni15Si5 amorphous alloys were found to exhibit a better corrosion resistance evaluated by potentiodynamic polarization measurements in 3.5wt% NaCl solution.

並列關鍵字

Mechanical alloying ； Cu-based amorphous alloy ； Supercooled liquid region ； Vacuum hot pressing

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