Defects encountered in aluminum alloy die castings include flow marks, patterns, cold seals, dents, bubbles, pores, pinholes, shrinkage cavities, porosity, etc.
- Flow marks and patterns: Flow marks and patterns are traces left by the molten alloy that first enters the mold cavity, forming an extremely thin and uneven metal layer, which is compensated by the subsequent molten alloy.
- Cold isolation: Cold isolation is a gap where lower-temperature metal flows are connected but not fused.
- Depression: A depression is a concave part on the smooth surface of a die-casting part, and its surface is in a natural cooling state.
- Bubbles: Bubbles are bubbles formed by the expansion of accumulated gas under the surface of the die casting.
- Air holes and pinholes: Air holes and pinholes are holes with a regular shape, a smooth surface, and a dark gray surface formed by the gas involved in the die casting.
- Shrinkage cavities and porosity: Shrinkage cavities and porosity are holes with irregular shapes and rough surfaces caused by insufficient internal compensation during the condensation process of die castings.