Ceramic has become the material of choice for smart wear due to its scratch-proof, skin-friendly, non-allergic, jade color and low cost. And ceramic injection molding is one of the main molding processes of intelligent wearable ceramic appearance parts.
Ceramic injection molding process
Ceramic injection molding is a near net size plastic molding method developed on the basis of polymer injection molding technology. The basic process of intelligent wearable ceramic injection molding mainly includes four stages: feeding preparation, injection molding, degreasing and sintering.
1. Feed preparation The yttrium stabilized zirconia powder and surfactant are weighed in proportion, ethanol is added, then mixed by ball milling, dried and screened to obtain slurry, and then mixed with binder, mixed and granulated to obtain feed for injection.
Key to feed preparation:
Select the appropriate binder, binder and ceramic powder compatibility and shear dispersion good, eliminate agglomeration;
Appropriate binder content, so that the feed has good fluidity;
Increased ceramic powder loading (solid content) and reduced dimensional deformation.
2, injection molding will be injection molding feed placed in the injection molding machine, heated into a viscous melt, at a certain temperature and pressure high-speed injection into the metal mold, cooling after stripping out to get ceramic billet body. The key to injection molding:
Reasonable mold design and processing (gate, runner, precision, material, etc.)
Setting and optimization of injection parameters (temperature, pressure, mold temperature)
Exhaust and body stress during mold filling
3, degreasing degreasing is the process of removing the binder component in the injection molding ceramic billet by physical or chemical methods. Due to the different binder system, degreasing process is different, injection molding ceramic degreasing methods include: thermal degreasing, solvent degreasing, catalytic degreasing, select the efficient and safe degreasing technology for degreasing, get blank.
4. Sintering
The ceramic blank was sintered at a high temperature of 1300°C~1800°C. Sintering is a process of forming ceramic billet. A large part of the performance of ceramic products is determined by sintering. Zirconia ceramics need high density and uniform sintering, not only the degreasing process is very important, but also affected by powder, additives, sintering temperature and time, pressure and sintering atmosphere and other factors.
Advantages of ceramic injection molding
Intelligent wearable ceramic appearance parts include ceramic watch case, ceramic bezel, ceramic dial, ceramic bottom cover, ceramic crown, ceramic watch chain and other products, small size, high precision requirements.
The advantages of using ceramic injection molding for intelligent wearable ceramic appearance parts are:
Can be close to the net molding geometry complex and have special requirements of small ceramic parts, high precision molding products, green density uniform, high strength, sintered body performance and product quality consistency is good, so that sintered ceramic products without machining or less processing, so as to reduce the expensive ceramic processing costs;
The molding process has a high degree of mechanization and automation, the molding cycle is short, the management and control of the production process is also very convenient, easy to achieve mass production, large-scale production;
The molded ceramic products have extremely high dimensional accuracy and surface finish, the surface finish can reach 5um. Therefore, CIM ceramic injection molding technology has become one of the forming methods of existing ceramic forming technology.
Post time: Jan-06-2023