Microstructure,hardness,tensile,and wear properties of Cu/Al-Al 2 O 3 laminar composites prepared by gas pressure infiltration casting and roll bonding processes

Abstract

Owing to specific properties and applications of metal-ceramic composites, they are nowadays being produced by various processes. Here, gas pressure infiltration casting and cold roll bonding were used to produce Cu/Al-Al₂O₃/Cu with different volume fractions of Al₂O₃ whiskers. The findings showed flawless interfaces of Cu/Al-Al₂O₃, indicating good interfacial bonding. Also, based on optical microscopy (OM) and scanning electron microscopy (SEM) results, the median size of grains in cast Al-Al₂O₃ decreased as the volume fraction of cast composite increased. Similarly, the median size of Cu grains decreased from 10.2 µm in Cu/Al-Al₂O₃(5% vol)/Cu to 8.7 µm in Cu/Al-Al₂O₃(25% vol)/Cu. On the contrary, the strength and hardness results showed a growth as whiskers increased. The hardness increased from 122 HV and 58 HV on Cu and Al-Al₂O₃ (5% vol) layers of Cu/Al-Al₂O₃(5% vol)/Cu to 134 HV and 72 HV on Cu and Al-Al₂O₃(25% vol) of Cu/Al- Al₂O₃(25% vol). Also, the mass loss and wear rate of Cu/ Al-Al₂O₃/Cu composites decreased as more whiskers were used. The worn surfaces on composites showed different amounts of grooves and debris which were decreased as whiskers increased.