Correlation between the thermal responses and microstructure patterns in aluminum‐based silicon carbide composites (SiC_p/Al) consolidated by different high pressure torsion schemes

Abstract

High pressure torsion of powder mixture is a novel strategy for manufacturing high‐quality aluminum‐based silicon carbide composite SiCp/Al billet used in electronic packaging, however, the correlation between thermal properties and the high pressure torsion process and the related mechanisms are still unclear. To this end, the variation rules of thermal expansion coefficient and thermal conductivity with high pressure torsion turns are studied and the corresponding microstructure morphology and dislocation patterns are observed by optical and transmission electron microscopes. The results show that thermal expansion coefficient decreases monotonically but thermal conductivity first increases then decreases with the increase of high pressure torsion turns. Moreover, the results of differential scanning calorimetry experiments indicate the decrease of recrystallization temperature with turns of high pressure torsion. The non‐monotonic variation of thermal conductivity is attributed to the combined effect of the improved relative mass density brought by the consolidation effect and the dislocation tanglement and pattern transformation (formation of in‐situ sub‐grains) during high pressure torsion process.

Finite element analysis and experimental investigation of ultrasonic testing of internal defects in SiCp/Al composites

“…Silicon carbide particle-reinforced aluminum metal matrix composites (SiCp/Al) are widely used in fields of aerospace, electronic engineering and optical instruments, due to their unique mechanical and physical properties such as low thermal expansion, high specific stiffness and high wear resistance [1][2][3]. While internal defects such as voids, cracks, inclusions and particle clustering are inevitable generated during the synthesis and subsequent manufacturing processes of SiCp/Al composites [4,5], the pre-existing internal defects have a strong impact on the mechanical properties and performance of SiCp/Al-based components [6,7].…”

Finite Element Investigation of the Influence of SiC Particle Distribution on Diamond Cutting of SiCp/Al Composites

“…Aluminum-based silicon carbide composites (SiCp/Al) have been widely used in the aerospace, automotive, machinery, and electronics industries for their unique physical and mechanical properties [1][2][3]. While mechanical machining is normally required to achieve desired shapes with considerable accuracy, recently cutting technique has also been proposed to process SiCp/Al composites for its high geometrical accuracy and high efficiency [4].…”