Die casting, as an important process in the manufacturing of mobile phone frames, accounts for a large proportion of mobile phone frame manufacturing due to its advantages of high output and low cost. According to Manager Wang from Laikebao Chemical, improved new die-casting processes such as bimetallic die-casting may further reduce the manufacturing cost of mobile phones. The use of die-casting release agents is an important means to ensure the yield of die-casting, and the correct selection of release agents is extremely important for die-casting manufacturers!
Die casting release agent is a functional substance between the mold and the finished product, which is a type of processing aid that prevents metal molded products from sticking to the mold and makes the die casting easy to detach. Due to the rapid development of die-casting technology, the amount of mold release agent has also significantly increased.
What are the classifications of release agents?
1TheClassified by composition, commonly used release agents are inorganic, organic, and high polymer.
1) Inorganic release agents, such as talcum powder, mica powder, clay, and white clay, are mainly used as composite materials for rubber processing film and semi-finished product release agents.
2) Organic release agents include fatty acid soaps (potassium soap, sodium soap, ammonium soap, zinc soap, etc.), fatty acids, paraffin wax, glycerin, Vaseline, etc.
3) High polymer release agents, including silicone oil, polyethylene glycol, low molecular weight polyethylene, etc., have much better release agent efficiency and thermal stability than organic release agents.
2TheClassified by physical state
According to the physical state of the release agent, it is usually divided into powder, semi-solid, and liquid. Powder and semi-solid can be applied to the surface of the mold like wax by brush or hand. The liquid can be applied to the surface of the mold with tools such as spray or brush to form an isolation film. Spraying is preferred for liquid release agents.
How do mobile phone die-casting manufacturers choose release agents? It is crucial to choose a high-quality die-casting release agent during the die-casting process of the phone frame/shell. Due to poor release agents, defects such as mold sticking, porosity, scaling/carbon deposition inside the cavity, cold insulation, and white spots may occur.
The key points for selecting release agents are:
1. Good moldability, the surface tension of spray release agent should be between 17 and 23 N/m;
2. Has heat resistance and does not undergo carbonization or decomposition when heated;
3. Stable chemical performance, no chemical reaction with molded products;
4. Does not affect the secondary processing performance of die-casting;
5. Non corrosive molds, non polluting products, low odor and toxicity;
6. Smooth and aesthetically pleasing appearance;
7. Easy to apply, high production efficiency.
