... /zinc alloy/4. Process: Die casting, Deburring, Drilling holes, Tapping, CNC Machining and Assembly.5. Surface treatment: Sandblasting, Tumbling, Powder coating, Wet ... /zinc alloy/4. Process: Die casting, Deburring, Drilling holes, Tapping, CNC Machining and Assembly.5. Surface treatment: Sandblasting, Tumbling, Powder coating, Wet ...