Release agent for metal die casting is a kind of functional substances between mould and products. It is a processing agent used to prevent metal mould products from adhering to moulds, easy for separation. For die casting technology highly development, the dosage of release agent is also increased drastically.
Release agent in common use includes inorganics, organics and superpolymer.
Inorganic release agent
Such as talcum powder, mica powder and compounds whose main ingredients are argil and white clay. The agent is used as film in rubber processing and separant for preventing semi-finished products from bonding.
Organic release agent
Organic release agent includes fatty acid soap, fatty acid, paraffin, glycerinum, Vaseline, etc.
The third release agent is superpolymer, containing silicone oil, polyethylene glycol, LMWPE, etc. The efficiency and heat stability are better than those of organic release agent.
Release agent is generally classified into powdery, semisolid and liquid. Powdery and semisolid can be smeared on the surface of mould by using hairbrush or hand just like ceroid. Liquid can be smeared by using spray or hairbrush, forming isolating membrane. For liquid, spray is the best.
Features of release agent:
1. Good demoulding deformation. For spray release agent, the surface tension should be located between 17 and 23 N/m.
2. Having heat resistance; carbonized decomposition will not occur when the agent is heated.
3. Steady chemical properties; will not cause chemical reaction with products.
4. Will not influence the second processing performance of die casting.
5. Will not corrode moulds or pollute products; having less odor and toxicity.
6. Having smooth and beautiful appearance.
7. Easy for smearing; having high production efficiency.