The stamping essentials of non-metallic materials such as plastics are different from steel plates.

When it comes to stamping, the most common is the stamping of metal materials, but the stamping process is also widely used in plastics and other non-metallic materials industries, but there are several considerations when stamping non-metal materials. Share the stamping essentials of non-metallic materials such as plastics, which are different from steel plates! 1. Non-metallic stamping such as plastic requires special molds such as wood, felt, leather, rubber sheet, paper, cotton fabric, plastic film and other non-metallic materials. General flat punches cannot be used for punching or blanking, and sharp-edged stamping molds are commonly used. . The structure of the sharp-edged punching die is composed of a die handle, a blanking die, an ejector and a connecting fastener, while the lower die has only a wooden backing plate, which is placed or fixed on the worktable. The sharp-edged punch (or die) is made of medium carbon steel (such as 45 steel) or carbon tool steel, or it can be made of hardened steel strip, the sharp edge of the cutting edge is about 10-30. When used for blanking, the bevel angle is inclined outward, when used for punching, the bevel angle is inclined inward. In order to prevent the blade from becoming blunt and chipping, hard wood, cardboard or polyurethane rubber is used under the punched material. Since the sharp-edged punch is easily damaged, the convenience of its assembly, disassembly, manufacturing and maintenance should be considered. Second, brittle plastic materials such as plexiglass need to be heated and stamped. Non-metallic materials are very different from metal materials in terms of mechanical properties and chemical composition, and their stamping methods are different from metal stamping methods. For brittle materials or laminated non-metallic materials with a thickness greater than 1mm, such as plexiglass, hard rubber sheets, phenolic resin laminates, etc., cannot be stamped at room temperature, because this will easily cause material cracking and delamination during stamping, and heating stamping is used Good quality stamping parts can be obtained. For 1mm thick plexiglass, the blank heating temperature is 60~80℃, the heating time is 1.5min, and the mold heating temperature is 90-110℃; for the hard rubber plate, the blank heating temperature is 60-80℃. 3. When non-metallic stamping, the stamping gap should not be too large. There are many types of non-metallic materials, such as plastic, cardboard, rubber, leather, plywood, and so on. In particular, the proportion of various plastics in the manufacture of automobiles and home appliances is rapidly increasing. Therefore, the shear processing of plastics is widely used. According to different types of plastics, the shear separation conditions of thermoplastics are also different. Materials such as propylene have good toughness, and the shear surface material is separated due to tensile force. Polyvinyl chloride is a kind of material, the material is relatively brittle, it is cut off due to the common cracks. For materials such as polycarbonate, the shear surface material is separated by crack growth and secondary shearing, which is similar to the separation of ductile metals with small gaps. In the above three cases, a small gap is used (the gap between the two sides is about 5% of the material thickness), and the material is supported and clamped. For the stamping of thermosetting plastics such as phenolic resin, laminates, and mica, delamination or delamination will occur during stamping, and defects such as swelling, discoloration, and cracking will occur near the stamping outline, resulting in unsmooth cut surfaces and small holes. This is especially true. For this reason, in addition to the stamping gap should be controlled at 1%-5%, heating stamping can also greatly reduce the defects of the shear surface. Fourth, when stamping plastics, avoid oblique stamping of non-metallic materials such as plastics, felt, leather, paper, rubber, etc., and sharp-edged punches are often used. However, it should be noted that when stamping plastics, the stamping gap is very small. At this time, if the punching die blade is not perpendicular to the material, but is inclined, the punching punch blade is not balanced due to the unbalanced force and the plastic material is easy to slide, which is easy to make the punch The cutting edge is cracked. Previous post: How to cleverly apply inorganic binders when assembling stamping dies