Characteristics: In the process of condensation casting, the shape is irregular due to insufficient internal compensation, and the surface is rough.
Features: The smooth stripe on the surface of the casting is visible to the naked eye, but it can not be felt by hand. The color is different from the texture of the base metal. It can be removed with a few rubs of 0# abrasive cloth.
Characteristics: The alloy matrix on the casting is broken or broken to form a filament-like gap, which has two kinds of penetration and non-penetration.
Cracks can be divided into cold cracks and hot cracks. Their main difference is that the metal at the crack of the cold crack casting is not oxidized, and the metal at the crack of the hot crack casting is oxidized.
10. Under-casting, insufficient pouring, unclear outline, and corner defects
Characteristics: The molten metal is not filled with the cavity, and the incomplete filling portion appears on the casting.
11. Imprints, putt impressions, inserts or moving blocks splicing impressions
Features: The surface of the casting is exposed by the mold cavity and the protruding and concave marks left by the splicing of the push rod, the insert, the movable block and the like.