The lower the porosity of the part and the better the mechanical properties

Generally, the smaller the resin particle size, the lower the porosity of the part and the better the mechanical properties. From the perspective of convenience and economy, we choose SFX-1 material from Shanghai Chemical Plant. If the resin is processed below the transition point, when the temperature changes around 10°C, the volume of the preform will change by 1%.

The selected F4 resin requires a white appearance, uniform texture, no impurities, and low thermal weight loss. The raw material used for winding parts is mainly F4 suspension polymer BBQ grill mat resin.Therefore, the temperature of F4 raw material should be adjusted before molding. can meet the requirements.

The adjustment method is to place the container with the raw materials in an environment of 23°C-25°C for 24h-48h before use. Since F4 is a crystalline polymer, 19°C is its primary transformation point. At this temperature, the crystalline structure will change significantly., Ltd. This change is often the cause of cracks in the product during sintering.

The pretreatment of raw materials includes temperature adjustment and crushing and screening. The preforming must also be carried out at this temperature. Generally, Polyflon M-12 produced by Japan's Daikin Company, Teflon 7A produced by Mitsui Company, and SFX-1 produced by the Electrochemical Plant of Shanghai Chlor-Alkali Chemical Co. F4 is a fibrous compound, which tends to clump during storage and transportation.

The pretreatment process must be carried out under very clean conditions to prevent impurities from affecting the appearance and other properties of the part. Due to the poor fluidity of F4 powder, it is not easy to distribute evenly during molding and feeding, so it must be crushed with a ramming machine before use, and then sieved with a 20-mesh screen