The phase transformation temperature, segregation behavior of elements and as-cast microstructure were investigated in experimental nickel-base superalloys with different levels of carbon and boron. The results show t...The phase transformation temperature, segregation behavior of elements and as-cast microstructure were investigated in experimental nickel-base superalloys with different levels of carbon and boron. The results show that the liquidus temperature decreases gradually but the carbide solvus temperature increases obviously with increasing carbon addition. Minor boron addition to the alloy decreases the liquidus temperature, carbide solvus temperature and solidus temperature slightly. Apart from rhenium, the segregation coefficients of the elements alter insignificantly with the addition of carbon. The segregation behavior of rhenium, tungsten and tantalum become more severe with boron addition. The volume fraction and size of primary carbides increase with increasing carbon addition. The main morphology of the carbides is script-like in the alloys with carbon addition while the carbide sheets tend to be concentrated and coarse in the boron-containing alloys展开更多
《密勒氏评论报》是美国专业报人来华创办的第一份亦是在日后影响最为深远的英文报纸,它历经军阀混战、国共内战、日军侵华战争时期,是中华民族浴血奋战到获得最后胜利的重要见证人。特别是次任主编约翰·本杰明·鲍威尔(John B...《密勒氏评论报》是美国专业报人来华创办的第一份亦是在日后影响最为深远的英文报纸,它历经军阀混战、国共内战、日军侵华战争时期,是中华民族浴血奋战到获得最后胜利的重要见证人。特别是次任主编约翰·本杰明·鲍威尔(John Benjamin Powell)于1922年收购该报并自任主编以来,始终坚持新闻自由与客观公正的原则,反对侵略、揭露暴行,引领该报在抗日战争期间实现了两次重大的报道立场转变。该报对世界认识中国、了解中国再到帮助中国起到了不可忽视的作用,为中国抗战的胜利争取到了国际声援并产生了深远的影响。展开更多
基金Projects(2011CB610406,2010CB631202)supported by the National Basic Research Program of ChinaProjects(51101120,50931004,51171151)supported by the National Natural Science Foundation of China
文摘The phase transformation temperature, segregation behavior of elements and as-cast microstructure were investigated in experimental nickel-base superalloys with different levels of carbon and boron. The results show that the liquidus temperature decreases gradually but the carbide solvus temperature increases obviously with increasing carbon addition. Minor boron addition to the alloy decreases the liquidus temperature, carbide solvus temperature and solidus temperature slightly. Apart from rhenium, the segregation coefficients of the elements alter insignificantly with the addition of carbon. The segregation behavior of rhenium, tungsten and tantalum become more severe with boron addition. The volume fraction and size of primary carbides increase with increasing carbon addition. The main morphology of the carbides is script-like in the alloys with carbon addition while the carbide sheets tend to be concentrated and coarse in the boron-containing alloys
文摘《密勒氏评论报》是美国专业报人来华创办的第一份亦是在日后影响最为深远的英文报纸,它历经军阀混战、国共内战、日军侵华战争时期,是中华民族浴血奋战到获得最后胜利的重要见证人。特别是次任主编约翰·本杰明·鲍威尔(John Benjamin Powell)于1922年收购该报并自任主编以来,始终坚持新闻自由与客观公正的原则,反对侵略、揭露暴行,引领该报在抗日战争期间实现了两次重大的报道立场转变。该报对世界认识中国、了解中国再到帮助中国起到了不可忽视的作用,为中国抗战的胜利争取到了国际声援并产生了深远的影响。
