Repair of Damaged Mold Surface by Cold-Spray Method

Thermal-mechanical loads during molding can cause wearing of the surfaces of the molds. In this research, a mold repair technique at low temperature was developed by applying cold-spray deposition. Aluminum particles were deposited on top of the damaged aluminum mold. The original mold surface was recovered by milling the deposited material. Material properties such as hardness, coefficient of thermal expansion, chemical composition, wear resistance, and machinability of the mold and repaired layer were characterized. To verify the recovered molding capability, polymer (Polystyrol) products were fabricated by injection molding using the repaired mold. Experimental results showed that the mold repair process using cold-spray deposition and machining can be applied in the mold repair industry.