The formation and growth of thermal fatigue crack in chromium wear resistant cast iron was investigated, and the effect of hot deformation on the crack was analyzed by means of optical microscope and scanning electron...The formation and growth of thermal fatigue crack in chromium wear resistant cast iron was investigated, and the effect of hot deformation on the crack was analyzed by means of optical microscope and scanning electron microscope and high frequency induction thermal fatigue tester. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, hot deformation can improve the eutectic carbiders morphology and distribution, inhibit the generation and propagation of thermal fatigue cracks. In the experiment, the propagation rate of thermal fatigue crack reduces with the quantity of hot deformation increasing, which was analyzed in the point view of the activation energy of crack propagation.展开更多
本文以用于成品机架的WC-6%Co(文中含量均为质量分数)硬质合金辊环为研究对象,在其轧制400 T 80A帘线钢线材后,根据轧槽的表面形貌、金相显微组织和裂纹扩展情况对热疲劳裂纹特征进行了分析;结合轧制工况条件,对热疲劳裂纹的形成进行了...本文以用于成品机架的WC-6%Co(文中含量均为质量分数)硬质合金辊环为研究对象,在其轧制400 T 80A帘线钢线材后,根据轧槽的表面形貌、金相显微组织和裂纹扩展情况对热疲劳裂纹特征进行了分析;结合轧制工况条件,对热疲劳裂纹的形成进行了讨论。分析结果表明:WC-6%Co硬质合金辊环轧槽表面上并未出现明显的龟裂纹,轧槽上的热疲劳裂纹细小且浅;轧制过程中的磨损、氧化、粘结相元素的扩散和冷却水的冲刷等因素的共同作用导致了材料中的WC晶粒的碎化和剥落而形成凹坑;热裂纹在向轧槽内部扩展过程中,以粗大WC晶粒的穿晶断裂为主;辊环材料的高的导热性和断裂韧性能够抑制热疲劳裂纹的萌生和扩展。展开更多
基金ItemSponsored by Guiding Programof Science and Technology Research of Jilin Province of China (20000513)
文摘The formation and growth of thermal fatigue crack in chromium wear resistant cast iron was investigated, and the effect of hot deformation on the crack was analyzed by means of optical microscope and scanning electron microscope and high frequency induction thermal fatigue tester. The results show that eutectic carbide is the main location and passage for initiation and extension of thermal fatigue cracks, hot deformation can improve the eutectic carbiders morphology and distribution, inhibit the generation and propagation of thermal fatigue cracks. In the experiment, the propagation rate of thermal fatigue crack reduces with the quantity of hot deformation increasing, which was analyzed in the point view of the activation energy of crack propagation.
文摘本文以用于成品机架的WC-6%Co(文中含量均为质量分数)硬质合金辊环为研究对象,在其轧制400 T 80A帘线钢线材后,根据轧槽的表面形貌、金相显微组织和裂纹扩展情况对热疲劳裂纹特征进行了分析;结合轧制工况条件,对热疲劳裂纹的形成进行了讨论。分析结果表明:WC-6%Co硬质合金辊环轧槽表面上并未出现明显的龟裂纹,轧槽上的热疲劳裂纹细小且浅;轧制过程中的磨损、氧化、粘结相元素的扩散和冷却水的冲刷等因素的共同作用导致了材料中的WC晶粒的碎化和剥落而形成凹坑;热裂纹在向轧槽内部扩展过程中,以粗大WC晶粒的穿晶断裂为主;辊环材料的高的导热性和断裂韧性能够抑制热疲劳裂纹的萌生和扩展。
