Establishing process, design parameters for permanent mold cast lead-free copper alloys

The mechanical, wear and corrosive properties of 14 lead-free copper alloys was studied. The design parameter like tensile properties, fatigue, fracture and impact toughness, wear and corrosion resistance of the lead-free copper alloys was investigated to evaluate patternmaker's shrinkage and taper allowances. The process parameters like mold material, gating design, mold coating, casting fluidity and alloy development were also studied. The shrinkage measurements indicated that thermal expansion of metal core in permanent mold casting forced the casting to mold wall and reduced effectiveness of core taper. The corrosion resistance of all copper-base alloys in permanent mold cast condition was better compared to sand cast condition.