旋压变形量对B4C增强铝基复合管微观组织及力学性能的影响

Influence of spinning deformation on microstructures and tensile properties ofB4C particulate reinforced aluminium matrix composite tube

摘要:

本文采用等离子放电烧结+异步错距旋压方法制备了不同旋压变形量的B₄C颗粒含量为10wt.%的铝基复合材料管材,研究了变形量对复合管材微观组织和力学性能的影响。 研究结果表明:随着旋压变形量的增加,B₄C铝基复合管材内部B₄C颗粒分布由类似网状结构变为均匀分布,B₄C颗粒与基体铝合金之间界面形成了冶金结合；等离子放电烧结过程中的颗粒之间的“尖端放电”效应使得颗粒之间的界面处产生局部高温,促进了界面之间的结合,在界面处产生了AlB₂和Al₃BC金属间化合物；旋压变形量的增加,细化了铝合金的晶粒尺寸,减小了B₄C的颗粒尺寸,但旋压过程中导致的大尺寸B₄C颗粒的断裂弱化了细晶强化和颗粒强化对抗拉强度的作用。

Abstract:

In this study,the B₄C particles reinforced aluminium matrix composite tube with different deformation was first fabricated by spark plasma sintering (SPS) and followed by asynchronous offset spinning. It was found that the B₄C particles distributed change from net to relatively homogeneously in the aluminium matrix with the spun deformation increase. The interface between B₄C and aluminium was formatted metallurgical bonding due to the discharge was happened lead to the local high temperature existed during SPS processing and the interface was mainly consisted of AlB₂ and Al₃BC phase. With the deformation increasing, the aluminium grain and B₄C size was decrease. But, large size of B₄C particles fracture was decrease the fine-grain and particles strengthening function for the tensile strengthening.