Semi-Solid Precision Forming Process of High-Strength and Wear-Resistant Aluminum Matrix Composites

Abstract

A layered composite structural model with an outer wear-resistant layer of high-silicon aluminum alloy and an inner layer of ultra-high strength aluminum alloy is designed. A scaling brake drum part with layered composite was prepared by semi-solid precision forming process. The effects of process parameters such as casting temperature, specific pressure, solid layer temperature and heattreatment system on the composite interface were investigated. The results show that the casting temperature and solid layer temperature had a great influence on the interface recombination. The high forming specific pressure could effectively restrain the growth of secondary dendritesof the composite, and the proper heat treatment process could improve the morphology of the composite interface. A scaling brake drum component with A390/7050 layered composite structure was well prepared under optimal conditions.

Study on Rheological Squeeze Casting Process of Ultra-high Strength Al-11Zn-1.8Mg-0.9Cu-0.15Zr-0.15Sc Alloy

“…A new Al-11Zn-1.8Mg-0.9Cu-0.15Zr-0.15Sc alloy was developed, which has good casting and mechanical properties, and it is easier to cast in comparison with the traditional 7xxx wrought alloy [7] . Meanwhile, a new rheological squeeze casting method was developed [8] , where the melt treatment by annular electromagnetic stirring (A-EMS) is used to homogenize the alloy melt before the melt is poured into the mold for squeeze casting, and the temperature field, component field and solidification structure can be homogenized greatly, which also benefits for further improving its casting performance. However, little work has been done to explore the optimal technological parameters of the rheological squeeze casting process of the Al-11Zn-1.8Mg-0.9Cu-0.15Zr-0.15Sc alloy.…”

Numerical Simulation and Experimental Study on Compound Casting of Layered Aluminum Matrix Composite Brake Drum

“…In a previous study by the author [ 26 ], the layered composite brake drum parts of 7050 aluminum alloy and A390 aluminum alloy were prepared by a liquid die forging compound casting method. It was found that the preheating temperature of solid and casting temperature of melt are the main factors affecting the interface bonding state.…”