SMC composite sheet is a very common material, so what are the technological processes? Let me introduce to you below:
1) Feeding: According to the need to insert a certain amount of information into the mold, the amount of feeding directly affects the density and size of the finished product. If the feeding amount is large, the finished product will have thick burrs, poor dimensional accuracy, and it is difficult to demould, and the smc composite material sheet may damage the mold; if the feeding amount is small, the finished product will not be close, and the brilliance will be poor, resulting in material shortage and waste.
2) Clamping: After feeding, even if the male and female molds are related. When the mold is closed, use Hurry first, and then change it to Slow when the Yin and Yang molds are engaged. The operation method of fast first and then slow is good for shrinking non-production time, preventing mold damage, and avoiding the material in the mold groove being worn out by the atmosphere due to too fast mold clamping, so that the insert is displaced and the molding rod is damaged. After the mold is closed, the pressure can be increased to heat and pressurize the material.
3) Exhaust: When molding thermosetting plastics, moisture and short molecules are often released. In order to eliminate these short molecules, evaporation and in-mold atmosphere, after the plastic reflection in the mold cavity of the plastic mold is held to a suitable time, Releasing pressure release mold exhaust for a short period of time. The exhaust operation can shorten the curing time and spread the physical lag instinct of the finished product, avoiding delamination and slow foaming in the finished product; The solidified gas on the surface of the material is not discharged.
4) Curing: The curing of thermosetting plastics is maintained for a period of time at the molding temperature, and the smc composite material sheet makes the polycondensation reaction of the resin reach the required connection level, so that the finished product has the required physical stiffness. Plastics with a low curing rate can also be temporarily suspended when the finished product can be completely demolded, and then use post-processing to complete the entire curing process; in order to increase the utilization rate of equipment. During molding and curing, it is often time to keep pressure and keep warm, generally 30 seconds to several minutes, and generally no more than 30 minutes. Too long or too short curing time has an effect on the instinct of the finished product.
5) Demoulding: demoulding is often completed by ejecting the rod. For finished products with forming rods or some inserts, the forming rods should be removed first with a Bomen tool, and then demolded.
6) Mold blowing: After demolding, the smc composite material sheet is often blown with a compressed atmosphere to blow the mold cavity and the mold surface of the mold. If the fixation on the mold is tight, it can also be cleaned with a copper knife or a copper brush, or even need to be cleaned with a copper knife or a copper brush. Polishing brush, etc.
7) Post-processing: In order to further popularize the quality of the finished product, the finished thermosetting plastics are often post-treated at a higher temperature after demoulding. Post-processing can make the plastic solidify more solid; reduce or eliminate the internal stress of the finished product at the same time, reduce the moisture and evaporation in the finished product, etc., which is beneficial to popularize the electrical performance and strength of the finished product.
Post time: Aug-23-2022