Yttria enhanced CuCr composites fabricated by laser powder bed fusion: Microstructure, properties and strengthening mechanisms

作者：Chengrui Xu, Haiou Zhuo, Jie Mao, Changzhi Sun, Ziyi Gong, Yan Chen, Li Ma, Jiancheng Tang · 发表于：Journal of Material Science and Technology · 年份：2025 · DOI：10.1016/j.jmst.2025.08.027 · 被引用次数：5 · 研究领域：Additive Manufacturing Materials and Processes、Additive Manufacturing and 3D Printing Technologies、High Entropy Alloys Studies

Complex and harsh service environments impose higher demands on comprehensive performance of high-strength and high-conductivity Cu-Cr series alloys. This work introduces Y 2 O 3 nanoparticles into CuCr alloy by the laser powder bed fusion (LPBF) process, aiming to further enhance its mechanical properties while preserving its electrical conductivity. The spherical Cu-0.7Cr-2Y 2 O 3 composite powders with excellent flowability are prepared using the spray drying and pre-sintering methods. Different laser powers and scanning speeds are utilized to optimize the LPBF forming processes. The CuCr-Y 2 O 3 composites with a high relative density of 99.4 % are successfully fabricated at a laser power of 250 W and a scanning speed of 400 mm/s. The effect of aging treatments on the evolution of the microstructure and properties of as-printed CuCr-Y 2 O 3 composites is systematically analyzed. In the LPBF samples, Y 2 O 3 particles with an average size of 46.7 nm are homogeneously dispersed in the copper matrix, and few Cr nano-precipitates are observed. Following aging treatment, the morphology and size of Y 2 O 3 particles remain consistent, while a greater density of Cr phases, with an average size of 7.3 nm, precipitate and exhibit a coherent interface relationship with the matrix. Aging treatment conducted at 460 °C for 1.5 h results in a peak tensile strength of 691.6 MPa, elongation of 21.5 %, electrical conductivity reaching 79.6 % IACS, microhardness values of 152.7 HV at room ...