Physical simulation of hot rolling of powder metallurgy-based Al/SiC composite by plane strain multi stage compression

Highlights: • Al/7vol.%SiC composite sheet produced using powder metallurgy and hot rolling. • Recrystallized, sub-structured grains are seen in the hot-rolled composite sheet. • A strain-compensated constitutive equation has been developed. • Both ductile and brittle fractures occurred with more dominant of ductility. • The temperature of 400 °C has been used to roll the composite and compared it with PSC. The development of lightweight materials like Al/SiC metal matrix composite sheet is a challenge by different manufacturing processes for further application in the automobile and aerospace industries. In the present work, plane strain multistage compression was used to investigate the hot rolling of powder metallurgy-based Al/7vol.%SiC composite. The cuboids of dimension (80 mm × 45 mm × 15 mm) from this composite material were synthesized using a conventional powder metallurgy technique. Then, the plane strain samples were cut from these composite cuboids. After that, plane strain multistage compression tests were performed using a thermo-mechanical simulator, Gleeble-3800. The multistage compression consists of six stages of different strains and all stages were compressed at a constant strain rate (1 s⁻¹) to achieve a final logarithmic strain of 1.5. All the plane strain stages were conducted at four different temperatures (350, 400, 450 and 500 °C). The flow curves obtained from the plane strain experiments show the initial hardening, then steady-state followed by final hardening. A constitutive equation for flow stresses has been developed and it predicts within the error of 2.62–6.18%. Then, the activation energy and dislocation densities are calculated and analyzed. Dislocation density is significantly high for this composite at the end of deformation as compared to the sintered one. After that, hot rolling experiments were conducted to make the Al/7vol.%SiC composite sheets. A comparative microstructural characterization has been examined using the optical image and electron backscatter diffraction. Recrystallized, deformed and sub-structured grains were observed in the hot-rolled sheet. The tensile fracture mechanisms are particle crack, void, growth and facet, whereas the edge crack in the plane strain samples due to particle crack and debonding. This study opens up the possible use of plane strain compression to design the hot rolling process in the industry for Al-metal matrix composites sheets.