【摘要】 研究了含1.55%Cu低碳钢在不同时效时间时的时效硬化行为。对经时效处理后的含铜高纯钢进行了显微硬度测试,应用金相显微镜(ZEISS)、X—射线衍射仪和JEM-2010型高分辨电子显微镜观察了含铜高纯钢等温时效过程的显微组织与结构,并分析了等温时效工艺与硬度、显微组织之间的对应关系。结果表明:时效温度越高,出现硬度峰值所需的时间越短,且峰值硬度也随之降低;550℃过时效阶段,铁素体晶粒中分布着大量的铜原子富集区,颗粒尺寸约20～72nm,随着等温时效时间的延长,富铜析出物不断粗化长大,从而导致硬度下降。更多还原

【Abstract】 Age-hardening behaviour of steel bearing 1.55-Cu was studied at different holding time.Microhardness testing during aging treatment in high purity steel bearing copper was carded out.By means of ZEISS metallographic microscope,X-ray diffractometer and JEM-2010 HREM,the microstructure of high purity steel beating copper during isothermal aging treatment was observed.The corresponding relationships between isothermal aging process and microhardness,microstructure were analyzed in this paper.The result showed that when aging temperature was increased,the holding time arriving at aging peak was shorter and the aging peak hardness was lower.At over-aging process of 550℃aging treatment,there were a large numbers of Cu-rich clusters distributed in the ferrite matrix,the size of which was about 20～72nm.With the holding time,the rich-copper particles were coarsened,and thus led to microhardness decreasing.更多还原