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Cu-15Ni-8Sn alloy having excellent characteristics of high strength, high conductivity, and high thermal stability, etc., is a promising new copper-based elastic material. However, the alloy due to the high content of the alloy elements of Sn, the use of the preparation of the traditional casting method, the solidification process of Sn is easy to produce serious dendritic segregation and macro inverse segregation. In addition, late alloy aging easy to produce discontinuous precipitation, lead to the strength, corrosion resistance and other properties of the alloy is greatly reduced. To solve the above problem, the rapid solidification technology introduced to the alloy preparation, add a fourth group element Si, while taking measures to inhibit the generation of discontinuous precipitation. This paper studies the common casting method and rapid solidification prepared, Cu-15Ni-8Sn-XSi alloys in the organizational structure, phase composition, phase change process and performance characteristics, rapid solidification process and add further analyzes the structure of the Si Alloy obtained with the performance of its mechanism of action, the following main conclusions: 1, compared with ordinary casting method, preparation of Cu-15Ni-8Sn-XSi alloys can grain is refined obviously rapid solidification, and can effective suppression of Sn element the dendrite segregation and macro-anti-segregation, so that the alloy optimization. 2 cast and rapid solidification add Si alloy Cu-15Ni-8Sn can play the effect of grain refinement. This is due to the added Si and Ni to form Ni 31 Si 12 phase and Ni 3 Si phase. Wherein NI 3 Si phase having the same structure as the base body, and close to the lattice constant, which has a role of the modificator, and thereby to make the grain refinement. With respect to the ordinary casting method using the the rapid solidification prepared Cu-15Ni-8Sn-XSi alloy, the Si crystal grains refinement effect is relatively weak, which is due to the fast cooling rate in the rapid solidification process makes more Si solid solution generated in the alloy matrix, so that the number of Ni-Si compound is small, and the fast cooling rate also procure majority Ni 3 Si solid solution in the alloy matrix, making the role of the modificator Ni 3 Si phase greatly reduce the number of. 3,850 ℃ × 2h solution treatment allows ordinary casting and rapid solidification of the γ-phase in the Cu-15Ni-8Sn-XSi cast alloy was completely dissolved in the alloy matrix. NI 3 Si phase in the solution heat treatment can be a solid solution in the matrix, while the of Ni 31 Si 12 phase fairly stable, the 850 ° C solid solution processing is not yet easy to be dissolved. For ordinary cast prepared alloy Cu-15Ni-8Sn-XSi, when the Si content is 0.3, i.e. since the Si and Ni to generate a large number of fine of Ni 31 Si 12 phase the alloy grain growth trend was significantly inhibited in the solution treatment process, and for the rapidly solidified alloy, due to the fast cooling rate of more Si in the form of alloying elements in solid solution in the alloy matrix, The generated amount of the compound of Ni-Si is relatively small, only when the Si
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