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铍铜合金性能优异,但潜存毒性危害,Cu-Ni-Sn合金是一种典型的调幅分解强化型弹性铜合金,凭借其高的强度、硬度、弹性和优良的抗应力松弛性能,广泛应用于电子、航天、航海等领域,是替代铍铜的候选材料之一。然而Cu-Ni-Sn合金体系复杂,不同成分合金的性能差异较大,传统的研究材料的方法,一次只能研究一种或几种成分的合金,因此本文选择了“扩散多元节”高通量实验方法对Cu-Ni-Sn合金进行研究。本文采用CALPHAD相图计算手段,计算了Cu,Ni和Sn元素在相变过程中的活度变化曲线,根据元素活度在合金相中的范围大小对Cu-Ni-Sn三元扩散偶的Cu-Ni,Cu-Cu35Sn和Ni-Cu35Sn各个界面的固相序列进行了理论优化。通过Cu-Ni-Sn三元扩散偶实验,获得了CuNi,Cu-Cu35Sn和Ni-Cu35Sn扩散界面的过渡层组织形貌,结合理论计算结果,得到了可能的界面固相序列。在650℃条件下,Cu-Ni界面处仅有fcc_A1相的过渡层;Cu-Cu35Sn界面过渡层固相序列自富Cu端为fcc_A1→D03_Cu3Sn/Cu3Sn;Ni-Cu35Sn界面的固相序列自富Ni端为fcc_A1+Ni3Sn_LT→fcc_A1+Ni3Sn2→Ni3Sn2+D03_Cu3Sn/Cu3Sn。
Beryllium copper alloy with excellent performance, but potentially toxic hazards, Cu-Ni-Sn alloy is a typical amplitude modulation decomposition enhanced elastic copper alloy, with its high strength, hardness, elasticity and excellent resistance to stress relaxation properties, widely used In electronics, aerospace, navigation and other fields, alternative beryllium copper is one of the candidate materials. However, the Cu-Ni-Sn alloy system is complex, and the performance of the alloys with different compositions is quite different. The traditional method for studying materials can only study alloys with one or several compositions at a time. Therefore, High-throughput experimental method for Cu-Ni-Sn alloy. In this paper, CALPHAD phase diagram is used to calculate the activity curve of Cu, Ni and Sn during phase transition. According to the range of elemental activity in the alloy phase, the Cu-Ni-Sn ternary diffusion pair Cu -Ni, Cu-Cu35Sn and Ni-Cu35Sn were optimized theoretically. The transitional layer morphology of CuNi, Cu-Cu35Sn and Ni-Cu35Sn diffusion interfaces was obtained by the Cu-Ni-Sn ternary diffusion couple experiment. By the theoretical calculation results, the possible interface solid phase sequences were obtained. At 650 ℃, there is only fcc_A1 phase transition layer at Cu-Ni interface. The solid phase sequence of Cu-Cu35Sn interfacial transition layer is fcc_A1 → D03_Cu3Sn / Cu3Sn. The solid-phase sequence of Ni-Cu35Sn interface is rich in Ni The end is fcc_A1 + Ni3Sn_LT → fcc_A1 + Ni3Sn2 → Ni3Sn2 + D03_Cu3Sn / Cu3Sn.