Cu-Ni-Al合金近平衡凝固过程中的析出相

Precipitated phase in Cu-Ni-Al alloy during near equilibrium solidification

采用近平衡凝固试验制备了Ni/Al原子比为3∶1的不同Cu含量的Cu-Ni-Al合金,并对其显微组织及相组成进行了分析。结果表明,不同Cu含量的Cu-Ni-Al合金显微组织由枝晶臂和晶间相组成,经XRD分析,二者均为富Cu相固溶体α-Cu(Ni,Al)。由于枝晶臂和晶间区域Ni、Al原子浓度不同,导致在随后的固态相变过程中枝晶臂区域Ni-Al析出相的数量和尺寸均明显大于晶间区域。

Cu-Ni-Al alloys with different contents of Cu and Ni/A1 atomic ratio 3：1 were prepared by near-equilibrium solidification, and microstrueture and phase composition of the alloy were analyzed. The results show that the microstructure of the tested alloys with different Cu contents are composed of dendrite arm and intercrystalline phase, which are Cu-rich phases （ ct-Cu（ Ni, A1） ） by XRD. Due to the different levels of Ni, Al atomic concentration in the dendrite arm and intercrytalline phase area, the number and size of Ni-Al precipitate in the dendrite arm area are significantly greater than intercrytalline phase during solid-state phase transformation.