目前广泛应用的含Cr的薄膜有Cr N薄膜,以及以Cr N薄膜为基础,通过添加Si和C元素形成的Cr Si N薄膜、Cr CN薄膜和Cr Si CN薄膜。综述上述4种薄膜的结构及其力学和摩擦学特性的研究进展,阐述在不同摩擦环境下掺杂元素含量对薄膜摩擦因数...目前广泛应用的含Cr的薄膜有Cr N薄膜,以及以Cr N薄膜为基础,通过添加Si和C元素形成的Cr Si N薄膜、Cr CN薄膜和Cr Si CN薄膜。综述上述4种薄膜的结构及其力学和摩擦学特性的研究进展,阐述在不同摩擦环境下掺杂元素含量对薄膜摩擦因数和磨损率的影响,指出Si和C元素的掺杂均能改善Cr N薄膜的摩擦学性能,并从结构角度分析其原因。展开更多
To investigate the effects of homogenizing and aging treatments on the microstructure of an Nb-Ti-Cr-Si based ultrahigh temperature alloy,coupons were homogenized at 1 200-1 500 °C for 24 h,and then aged at 1 000...To investigate the effects of homogenizing and aging treatments on the microstructure of an Nb-Ti-Cr-Si based ultrahigh temperature alloy,coupons were homogenized at 1 200-1 500 °C for 24 h,and then aged at 1 000 °C for 24 h.The results show that the heat-treated alloy is composed of Nb solid solution(Nbss),(Nb,X)5Si3 and Cr2Nb phases.With the increase of heat-treatment temperature,previous Nbss dendrites transformed into equiaxed grains,and petal-like Nbss/(Nb,X)5Si3 eutectic colonies gradually changed into small(Nb,X)5Si3 particles distributed in Nbss matrix.A drastic change occurred in the morphology of the Laves phase after homogenizing treatment.Previously coarse Cr2Nb blocks dissolved during homogenizing at temperature above 1 300 °C,and then much finer and crowded Cr2Nb flakes precipitated in the Nbss matrix in cooling.Aging treatment at 1 000 °C for 24 h led to further precipitation of fine particles of Laves phase in Nbss matrix and made the difference in concentrations of Ti,Hf and Al in Nbss,(Nb,X)5Si3 and Cr2Nb phases reduced.展开更多
基金"863"Project(2012AA09A203)Nature Science Founding of Shandong Province(Q2008F12)Fundamental Research Funds for the Central Universities(11CX04032A,11CX06069A)
文摘目前广泛应用的含Cr的薄膜有Cr N薄膜,以及以Cr N薄膜为基础,通过添加Si和C元素形成的Cr Si N薄膜、Cr CN薄膜和Cr Si CN薄膜。综述上述4种薄膜的结构及其力学和摩擦学特性的研究进展,阐述在不同摩擦环境下掺杂元素含量对薄膜摩擦因数和磨损率的影响,指出Si和C元素的掺杂均能改善Cr N薄膜的摩擦学性能,并从结构角度分析其原因。
基金Project (51071124) supported by the National Natural Science Foundation of ChinaProject (20096102110012) supported by the Ministry of Education, China Project (07-TP-2008) supported by the State Key Laboratory of Solidification Processing in Northwestern Polytechnical University,China
文摘To investigate the effects of homogenizing and aging treatments on the microstructure of an Nb-Ti-Cr-Si based ultrahigh temperature alloy,coupons were homogenized at 1 200-1 500 °C for 24 h,and then aged at 1 000 °C for 24 h.The results show that the heat-treated alloy is composed of Nb solid solution(Nbss),(Nb,X)5Si3 and Cr2Nb phases.With the increase of heat-treatment temperature,previous Nbss dendrites transformed into equiaxed grains,and petal-like Nbss/(Nb,X)5Si3 eutectic colonies gradually changed into small(Nb,X)5Si3 particles distributed in Nbss matrix.A drastic change occurred in the morphology of the Laves phase after homogenizing treatment.Previously coarse Cr2Nb blocks dissolved during homogenizing at temperature above 1 300 °C,and then much finer and crowded Cr2Nb flakes precipitated in the Nbss matrix in cooling.Aging treatment at 1 000 °C for 24 h led to further precipitation of fine particles of Laves phase in Nbss matrix and made the difference in concentrations of Ti,Hf and Al in Nbss,(Nb,X)5Si3 and Cr2Nb phases reduced.