Characteristics of Zinc Alloy Die Casting
Zinc alloy die casting is widely used in various decoration. The most common defect of zinc alloy die casting is surface blister. Defect characterization: there are bubbles on the surface of die-casting parts, which are found after die-casting, exposed after polishing or processing, or after oil spraying or electroplating.
Causes:
1, zinc alloy die casting caused by intergranular corrosion:
Harmsome impurities in zinc alloy composition: lead, cadmium, tin will gather at the grain boundary leading to intergranular corrosion, metal matrix is broken due to intergranular corrosion, and electroplating accelerates this evil, by intergranular corrosion parts will expand and the coating will be jacking, resulting in casting surface blisters. Especially in humid environment, intergranular corrosion will cause casting deformation, cracking and even broken.
2, zinc alloy die casting holes caused by:
The main mechanism is stomata and contraction, stomata tend to be round, and contraction is mostly irregular. (1) Causes of pores: In the process of filling and solidification of metal liquid A, holes are produced on the surface or inside of the casting due to gas intrusion. B Intrusion of gas volatilized from paint. C alloy liquid gas content is too high, solidification precipitation.