Effect of infiltrated eutectic AlSi on the microstructure and properties of C/C composites. (May 2021)

• Record Type: Journal Article
• Authors: Liu, Lei; Li, Boyan; Guo, Yongchun; Yao, Xiyuan; Yang, Wei; Feng, Wei; Chen, Xingyu; Wei, Xiaotian; Gao, Yu
• Is Part Of: Journal of composite materials. Volume 55:Number 10(2021)
• Page Start: 1349
• Page End: 1357
• Publication Date: 2021-05
• Subjects: C/C composite -- Al matrix composites -- grain refinement -- pressure infiltration -- properties; Composite materials -- Periodicals; Composites -- Périodiques; 620.118
• DOI: 10.1177/0021998320969794
• Languages: English
• ISSNs: 0021-9983

Abstract

Eutectic AlSi alloy was pressure infiltrated into a porous C/C skeleton to develop a low cost new C/C composite for application without extreme high temperature. C/C composite possessed a density of 1.7 g/cm 3 was prepared for comparison. The effects of filling AlSi with and without Al-Ti-C grain refiner on the microstructure and properties of C/C composites were mainly studied. Result indicated that the introduced AlSi interpenetrated with C/C skeleton and made the composites compact. In comparison with C/C composite, the compressive strength and particle erosion resistance were greatly enhanced while the density and thermal expansion coefficient (CTE) increased slightly. After adding the refiner, Si network involved dendritic Al in C/C-AlSi was transformed to refined mixed AlSi, Al bulk and Si surrounded dendritic Al, and two kinds of micro-cracks came into being, which resulted in the decreased strength, improved erosion property and increased CTE of C/C-AlSiR . Both AlSi textures and micro-cracks in the modified C/C composites determined the crack propagation and led to their different compressive behaviors and anti-erosion abilities.