Cu-9.5Ni-2.3Sn-0.25Si合金铸态组织与时效性能的研究(续)

图4为Cu-9．5Ni-2．3Sn-0．25Si合金经400~C×4h时效后微观组织与扫描电镜照片。由图4（a）中可以看出：合金经70％的冷变形时效后，合金晶粒组织明显破碎，并有大量的第二相小颗粒析出，而且分布均匀。

Study on As-Cast Structure and Properties of Aging Treatment of the Cu-9.5Ni-2.3Sn-0.25Si Alloy

In this experiment, some testing methods which include metallographic optical microscope, SEM,EDS MinifleX - ray diffraction,SlGMASCOPE SMP]0 -type conductivity meter, Vickers hardness tester and so on were used to study the microstructures of as -cast and after aged,Conductivity,hardness of the Cu -9.5Ni- 2.3Sn alloy which added 0.25 （wt%） Si. The results show that the dendrite structure becomes obviously and it appears Ni2Si,Ni3Si,Ni3Sn,Ni4Sn phase as - cast. Cu - 9.5Ni-2.3Sn -0.25Si alloy will be strengthened because of the formation of Ni2Si and Ni3Si new phases by the means of rejecting the grain growing and aging deposition after aged at 400~~; x 4h. The conductivity with aging the extension of time and the temperature increases have been increasing after aged, then increase became slowly; the curve of hardness of alloy against aging time and temperature is the single peak, and the curve with the extension of time and the temperature increases first increases, then decreases, the alloy aging treatment at 400C x 6 h has good properties.