Zhang Xiaoying, Zhang Xingpeng, Liu Wenbo, Jiang Aoke, Long Yu
School of Resources, Environment and Materials, Guangxi University, Nanning 530004, China.
State Key Laboratory of Featured Metal Materials and Life-Cycle Safety for Composite Structures, Guangxi University, Nanning 530004, China.
Materials (Basel). 2024 Apr 30;17(9):2121. doi: 10.3390/ma17092121.
A new approach is proposed that identifies three different zones of the Si-rich network structure (the cellular structure) in laser powder bed fused (LPBF) AlSi10Mg alloy, based on the variation in morphology, grain growth transition, and melt pool solidification conditions. The three identified zones are denoted in the present work as the liquid solidification zone (LSZ), the mushy solidification zone (MSZ), and the heat affected zone (HAZ). The LSZ is the result of liquid-solid transformation, showing small planar growth at the boundary and large cellular growth in the center, while the MSZ is related to a semisolid reaction, and the HAZ arises from a short-time aging process. The boundary between the LSZ and MSZ is identified by the change of grain growth direction and the Si-rich network advancing direction. The boundary between MSZ and HAZ is identified by the start of the breakdown of the Si-rich network. In addition, it is found that the fracture is generated in and propagates along the HAZ during tensile tests.
提出了一种新方法，该方法基于形态变化、晶粒生长转变和熔池凝固条件，识别激光粉末床熔融（LPBF）AlSi10Mg合金中富硅网络结构（蜂窝状结构）的三个不同区域。在本工作中，这三个识别出的区域分别被称为液固凝固区（LSZ）、糊状凝固区（MSZ）和热影响区（HAZ）。LSZ是液固转变的结果，在边界处显示出小平面生长，在中心处显示出大的胞状生长，而MSZ与半固态反应有关，HAZ则源于短时间时效过程。LSZ和MSZ之间的边界通过晶粒生长方向和富硅网络推进方向的变化来识别。MSZ和HAZ之间的边界通过富硅网络开始破裂来识别。此外，发现在拉伸试验期间，裂纹在HAZ中产生并沿HAZ扩展。
