Based on the physical state of the
Display Micro Screws reinforcement materials and the type of molding material used, molding processes can be categorized as follows:
1. Fiber Molding Method: Premixed or pre-impregnated fiber molding materials are placed into a molding machine; the composite product is formed within a metal mold under specific temperature and pressure conditions.
2. Chopped Fabric Molding Method: Scraps of glass fiber fabric or other resin-impregnated fabrics (such as hemp, organic fiber, asbestos, or cotton cloth) are cut into small pieces, then heated and compressed within a mold to form the composite product. This method is suitable for products with simple shapes and moderate performance requirements.
3. Fabric Molding Method: Two-dimensional or three-dimensional fabrics woven into the desired shape are impregnated with resin, then placed in a metal mold and subjected to heat and pressure to form the composite product.
4. Laminate Molding Method: Resin-impregnated glass fiber fabric or other fabrics are cut to the required shape, then heated or pressed within a metal mold to form the composite product.
5. Filament Winding Method: Continuous fibers or fabric strips impregnated with resin are wound onto a mandrel using a specialized winding machine under controlled tension and temperature; the assembly is then placed in a mold and heat-pressed to form the composite product.
6. Sheet Molding Method: Sheets are cut according to the product's dimensions, shape, and thickness; multiple layers are then placed into a metal mold and subjected to heat and pressure.
7. Preform Molding Method: A preform made of chopped fibers—approximating the final shape and size—is placed into a metal mold; a prepared binder (resin mixture) is then injected into the mold, and the assembly is molded under specific temperature and pressure conditions.
8. Directional Molding: Unidirectional prepreg is positioned along the direction of principal stress, followed by compression molding. This method allows for a fiber content of up to 70% and is suitable for products requiring high unidirectional strength.
9. Molding Powder Method: Molding powder is composed primarily of resin, fillers, curing agents, colorants, and mold release agents. The resins used are primarily thermosetting resins (such as phenolic, epoxy, and amino resins). Thermoplastic resins characterized by high molecular weight, poor flowability, and high melting temperatures—which are otherwise difficult to process via injection molding or extrusion—can also be formulated into molding powders. The molding process for these powders is essentially the same as that for other molding materials. The primary difference is that these powders do not contain reinforcing materials; consequently, the resulting products have lower strength and are mainly used for components subject to secondary loads.
10. Suction Preform Molding Method: This process involves using a suction technique (air suction or wet slurry suction) to form glass fibers into a preform that approximates the structure of the final product. This preform is then placed into a mold, resin is introduced, and the assembly is molded under specific temperature and pressure conditions. This method offers low material costs and accommodates both long and short fibers, making it suitable for products with complex shapes. While the process can be automated, the equipment costs are high.
