Research on the Mechanical Behavior and Deformation Failure Mechanism of SiC/AZ91D Composites with Particles Mixing Based on Actual Three Dimensional Microstructure(PDF)
MATERIALS CHINA[ISSN:1674-3962/CN:61-1473/TG]
Issue:
2025年08
Page:
770-777
Research Field:
Publishing date:
Info
Title:
Research on the Mechanical Behavior and Deformation Failure Mechanism of SiC/AZ91D Composites with Particles Mixing Based on Actual Three Dimensional Microstructure
Based on the real microstructure of the mixed particlesreinforced composites, the cohesive unit was introduced at the interface between the particles and the matrix, three finite element models with different particles mixing ratios were established, the mechanical behavior during uniaxial compression and deformation failure mechanism of the SiC/AZ91D composites were studied. The results show that the yield strength and compressive strength of the mixed particles-reinforced composites with equivalent particle sizes of 5 μm and 10 μm are greater than those of the single-particle reinforced composites, and the compression ratio is in the range of those of the two single-particle reinforced composites, particles mixing can delay the initiation and propagation of cracks in composite materials. The larger the 5 μm particle and 10 μm particle mixing volume ratio, the higher the yield strength, compressive strength and compression ratio of the composite; with the particle mixing volume ratio increasing, the initiation and propagation of cracks are more suppressed, the final crack length is longer. The mechanism of crack initiation and propagation of the composite materials is due to the serious stress concentration at the boundary and sharp corner of SiC particles group,resulting in matrix damage and microcrack initiation, and microcracks propagate and converge into main crack along the maximum shear stress direction.