Preparation of Cladding Billet via Direct Chill Casting Process

A mathematic model was built to describe the cladding casting process and the casting parametric influence on the cladding billet. The effect of casting speed, casting temperature and internal cooling water rate on the casting process performance was discussed. Based on the numerical simulation results, the cladding billet was prepared successfully. Moreover, the model was verified by the temperature measurements during the cladding casting process. The interfacial characteristics were investigated by metallographic examination, energy dispersive spectrometer and universal testing machine. The results show that there is a good agreement between the measured and calculated results. The comprehensively considered casting process is: casting speed 100 mm/min, internal cooling water rate 35 L/min, casting temperature 1020 K (AA4045) and 1000 K (AA3003). Based on the simulation results, the AA4045/AA3003 cladding billet with no defects and Φ140 mm/Φ110 mm in size is fabricated successfully. A diffusion layer with 15 μm in width is formed around the bonding interface. The interfacial bonding strength is 107.3 MPa, higher than that of AA3003, indicating that the two alloys have been bonded metallurgically.