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投稿时间:2017-09-24 修订日期:2017-09-24
投稿时间:2017-09-24 修订日期:2017-09-24
中文摘要: 使用激光熔覆设备制作了AlxTixCoCrCu0.5FeMoNi(x=4~5)涂层,使用王水对金相试样进行腐蚀,使用扫描电子显微镜、X射线衍射仪对涂层进行了分析。 结果表明,退火前涂层为BCC单相,超过700℃退火,基体BCC析出类Al2Ti3结构金属间化合物相。析出相在原晶界和晶粒中心形核。析出相含较多钼,相对于基底BCC相,析出相具有更好的耐王水侵蚀性。退火2小时,原子扩散距离小于1μm,约为晶粒尺寸的1/4。铝和钛的扩散属于普通的浓度梯度推动,而钼的扩散分为两步,第一步是铝钛金属间化合物周围的铜和钼扩散溶入铝钛金属化合物中,金属间化合物周围BCC相的铜和钼浓度下降,从而出现第二步较远距离的钼扩散过来补充金属间化合物周围的钼。
Abstract:AlxTixCoCrCu0.5FeMoNi(x=4~5)coating was made with laser cladding equipment. Aqua regia was employed to etch metallographic samples. The coating was investigated with scanning electron microscopy and X-ray diffractometre. It is shown that the coating was of BCC structure before annealing. After annealing at more than 700℃, Al2Ti3-like intermetallics phase was precipitated from BCC matrix phase. The precipitation formed crystal nuclei at both the boundary and center of crystal grains. Intermetallics precipitation phase contained more higher-atomic–number elements and had better corrosion resistance than BCC phase. After annealing for 2 hours, the atomic diffusion distance was less than 1μm, about a quarter of crystal grain size. The diffusion of both aluminum and titanium resulted from concentration gradient, while that of molybdenum included two steps. The first step was molybdenum atoms around aluminum/titanium precipitation diffused and dissolved in the precipitation. As a result, the concentration of molybdenum of BCC phase around the precipitation decreased, and all that lead to the second step that molybdenum atoms far from the precipitation diffused and replenished.
keywords: high-entropy alloy, thermokinetics, laser cladding, corrosion resistance, diffusion, chemically potential
文章编号: 中图分类号:TG113.25 文献标志码:
基金项目:广东省自然科学基金(2014A030313784)
引用文本:
温立哲,黄元盛,陈焕明.高熵合金析出相热动力学分析及组成相耐蚀性研究[J].有色金属工程,2018,8(6):.
温立哲,黄元盛,陈焕明.高熵合金析出相热动力学分析及组成相耐蚀性研究[J].有色金属工程,2018,8(6):.