最新色国产精品精品视频,中文字幕日韩一区二区不卡,亚洲有码转帖,夜夜躁日日躁狠狠久久av,中国凸偷窥xxxx自由视频

Ti(C,N)-based cermets containing 18 wt% and 38 wt% Ni–xCr (wt%, x=0, 10, 20, 30) were prepared by powder metallurgy, in order to study the effect of the composition and content of Ni–xCr binders on microstructure and mechanical properties of Ti(C,N)-based cermets. Ni-based binder phase and Ti-based carbonitride ceramic grains were observed in the other cermets, except that high-Mo and high-Cr white microstructure was also observed in cermet containing 38 wt% Ni–30Cr binder. There were often very fine white speckles in black core of ceramic grains for cermets with Cr-containing binder, especially at 38 wt% binder, and grey outer rim of ceramic grains became thicker when Cr content was high in binders. Regardless of binder content, hardness of cermets increased with increasing Cr content in binders, and the increase in hardness was more obvious at 38 wt% binder. At 18 wt% binder, transverse rupture strength and fracture toughness of cermets decreased with increasing Cr content in binders, however, at 38 wt% binder, they increased and then decreased with increasing Cr content in binders, and reached the peak at Ni–10Cr binder. Ceramic grain refinement led to the increase in the probability of intergranular fracture, and the synergistic effect of ceramic grain refinement, crack deflection, crack bridging, micro-crack toughening, etc., significantly improved transverse rupture strength and fracture toughness of Ti(C,N)-based cermets.