Properties and Microstructures of Ni60-WC composites prepared by Vacuum Sintering

• Main Authors: JASON CHEN, 陳?
• Other Authors: none
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/93253347089657869704

碩士 === 國立臺灣科技大學 === 機械工程系 === 104 === Composites based on nickel alloys and tungsten carbide (WC) have been widely used in various fields, due to high corrosion resistance of nickel alloys and the high wear resistance of tungsten carbide. Vacuum sintering process is an effective method for producing cemented carbides as the vacuum environment can prevent the materials from being oxidized and decarburized. In this study, composite materials composed of Ni60 (Ni/Cr/B/Si) and WC at various composition ratios (30.0 To 39.4 vol% WC) were sintered at different sintering temperatures (1125°C, 1150°C, 1175°C and 1200°C). Optimized results indicated that the composite with 30.0 vol% WC in the composite sintered at 1175 o C, a hardness as high as Hv 889 kgf / mm2 and a corrosion rate as low as 7.26 mg / cm2 / hr, tested using 70% sulfuric acid, can be achieved. The microstructural analysis based on XRD, SEM, and EDS indicated that Sintering temperature to 1200℃, will produce W2C and Ni2W4C, resulting in a decline Ni60-WC composite hardness and corrosion resistance.