INTERDIFFUSION ZONE CHARACTERISTICS OF INTERFACE BIMETAL ALUMINUM-COPPER PRODUCED BY SQUEEZE CASTING

Bimetals are metallurgical bonds formed by the mixing of two materials. One method of producing bimetal is through squeeze casting. However, there is currently no established optimal pressure reference for the pressing during bimetal production. This research aims to determine the optimal pressure in the form of bushings to achieve an optimal interdiffusion bond at the interface. The study uses copper and aluminum alloys. The melting temperature of the aluminum is set at 770°C, while the copper is 1150°C. The molten metals are alternately poured into a mold. In the first stage, aluminum is poured into the mold, followed by copper in the second stage, gradually forming an aluminum-copper bimetal bushing. In the third stage, pressure is applied. The squeeze pressure variations used are 30, 40, 50, and 60 MPa. The results show that increasing the squeeze casting pressure leads to an increase in the thickness of the interdiffusion layer. The highest hardness is observed in the interface because of the formation of AlCu compounds. The increase in hardness also enhances wear resistance in the interface. Therefore, squeeze casting with a pressure of 60 MPa is recommended for producing Al-Cu bimetal to achieve optimal interdiffusion at the interface.