Normally, some die-castings have airtightness requirements, with a focus on the internal density of the product. When customers observe numerous internal pores, they often assume it stems from high gas evolution of the release agent—but this is not the case. Gas in castings mainly originates from three sources:
Impurities or dissolved gases in the molten metal from improper smelting;
Air entrapment during the die-casting process (e.g., turbulent metal flow introducing air);
The release agent itself.
Since the primary goal is to evacuate gas from the mold, venting design and efficiency must also be evaluated. Multiple factors contribute to gas porosity—every step of the process demands attention.
If focusing specifically on the release agent, two key angles apply:
Release agent formulation: Whether the agent uses volatile raw materials that generate excessive gas during spraying. This requires collaboration with the supplier to adjust the formula.
Improper application: Such as over-concentrating the release agent or failing to dry it adequately. Excess agent or residual moisture evaporates into gas, exacerbating porosity—quantity often leads to quality degradation.
Of course, other factors (e.g., mold temperature, filling speed) should also be investigated.
For more information about 100 Questions (12): Is Excessive Internal Gas Porosity in Die-Castiings from release agents or die-casting auxiliary materials, and if you need customized die-casting release agent, please contact 15021483232 (same as Wechat)
