Effect of Rare Earth Y Addition on the Properties and Precipitation Morphology of Aged Cu-Cr-Ti Lead Frame Alloy
The influence of rare earth Y addition and ageing treatment on the properties and precipitation morphology of Cu-Cr-Ti alloy was investigated. The results show that 0.1wt%Y addition increases the hardness, and decreases the electrical conductivity slightly. However, both the hardness and electrical conductivity decrease with an excessive Y addition. After ageing at 550°C for 2h, Cu-0.3Cr-0.2Ti-0.1Y alloy has a good combination of the hardness and electrical conductivity, which has the hardness of 134HV and the electrical conductivity of 73.9%IACS. After ageing treatment, most Cr rich phases precipitate in the form of sphere shape while a small amount of Cr rich phases exist in the form of acicular, and Y rich phases precipitate in the form of flake along the grain boundary.
Zhengyi Jiang and Chunliang Zhang
X. H. Wang et al., "Effect of Rare Earth Y Addition on the Properties and Precipitation Morphology of Aged Cu-Cr-Ti Lead Frame Alloy", Advanced Materials Research, Vols. 97-101, pp. 578-581, 2010