微量硼对Cu_15Ni合金显微组织与力学性能的影响.pdfVIP

铸 造 May 2010 502 FOUNDRY Vol.59 No.5 · · 微量硼对Cu- 15Ni合金显微组织与力学性能的影响 董旭刚，金青林，林 波，赵 辉，高旭伟，蒋业华 （昆明理工大学材料与工程学院，云南昆明650093） 摘要：研究了不同B含量对Cu-15Ni合金显微组织、力学性能以及断口形貌的影响。结果表明，添加适量B能起到明显 的脱氧作用，且晶粒由粗大树枝晶变为细小等轴晶，铜镍合金的抗拉强度、伸长率和显微硬度得到提高。添加0.005% B时，合金的抗拉强度、伸长率和显微硬度分别由294 MPa、8%和HV 107提高到328 MPa、33.5%和HV 124 ；而进一步 增加B添加量时，Cu-15Ni合金的晶粒又由细小等轴晶变为粗大树枝晶，使得合金的抗拉强度、伸长率和显微硬度下降。 B 的加入并不改变Cu-15Ni合金的断裂机理，断裂机制仍为韧性断裂。 关键词：铜镍合金；硼；变质处理；力学性能 中图分类号： 文献标识码： 文章编号： TG146 A 1001-4977 （2010）05-0502-04 Effe ct of Tra ce Boron on Microstructure s and Me ch anica l P rop ertie s of Cu -15Ni Alloy DONG Xu-gang, JIN Qing-lin, LIN Bo, ZHAO Hui, GAO Xu-wei, JIANG Ye-hua （Faculty of Material Science and Engineering, Kunming University of Science and Technology, Kunming 650093, Yunnan, China） Ab stra ct ：It was investigated that the effects of B content on the microstructure, mechanical property and fractography of Cu-15Ni alloy. The results show that the B addition can effectively deoxidize the alloy melt and the microstructure of the alloy changes from coarse dendrite to small equiaxed dendrite. By addition of 0.005% B, the tensile strength, elongation and micro-hardness of Cu-15Ni alloys are improved from 294 MPa, 8% and HV 107 to 328 MPa, 33.5% and HV 124, respectively. Further increasing the addition amount resulted in a coarsening of grain structure. The fine dendrite grain again changed into coarse dendrite, which leads degradation of tensile properties and micro-