微量硼对Cu_15Ni合金显微组织与力学性能的影响.pdf

铸造 May 2010
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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。%
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、%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:TG146 文献标识码:A 文章编号:1001-4977 (2010) 05-0502-04
Effect of Trace Boron on Microstructures and
Mechanical Properties 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)
Abstract: 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 % B, the tensile strength, elongation and micro-hardness of
Cu-15Ni alloys are improved from 294 MPa, 8% and HV 107 to 328 MPa, % and HV 124,
respectively. Further increasing the addition amount resulted in a coarsening of grain structure. The
fine dendrite grain again changed into