Generally, modified polypropylene (P P) is selected as the material, which is composed of PP (about 60%), rubber (about 30%), filler (talc) about 9%, and additive (antioxidant, preservative, nucleating agent, anti ultraviolet agent, etc.) 1%. The material is resistant to low temperature impact (- 30 ℃, Izod impact strength is 6.0kg.cm/cm), with high fluidity and good sealing performance of coating (corresponding to E-10).

此外，该材料具有良好的外观质量，能够满足细熔合晶粒、良好的表面张力和无熔合晶粒的A级表面的要求。材料是可回收的，100%可回收。

In addition, the material has good appearance quality and can meet the requirements of fine fusion grain, good surface tension and A-class surface without fusion grain. The material is recyclable, 100% recyclable.

在产品设计阶段，利用MOLDFLOW软件对设计进行CAE分析，进行技术生产验证。分析内容包括:胶点位置、胶点尺寸、产品重量、锁模力、产品充装模拟、流场温度、充装压力、剪应力、收缩率、气体滞留位置、焊缝、翘曲、冷却液温度、零件温度。通过CAE分析，我们可以在设计阶段对产品的不良情况进行调整和预防，从而保证产品的顺利成型。

In the product design stage, use Moldflow software to carry out CAE analysis of the design and technical production verification. The analysis contents include: glue point position, glue point size, product weight, mold locking force, product filling simulation, flow field temperature, filling pressure, shear stress, shrinkage, gas retention position, weld, warpage, coolant temperature and maximum temperature of parts. Through CAE analysis, we can adjust and prevent the bad situation of the product in the design stage, so as to ensure the smooth formation of the product.

值得一提的是，保险杠并不是“等肉厚”设计，而是根据产品的不同部位需要进行“肉厚变化”，变化范围为2.6-3.4mm。一般原理是:中间部分属于厚肉区，胶嘴的远端为薄肉区，产品的汇合处为薄肉区。

It is worth mentioning that the bumper is not designed as "equal meat thickness", but "meat thickness change" according to different parts of the product, with the change range of 2.6-3.4mm. The general principle is: the middle part belongs to the thick meat area, the distal end of the glue mouth is the thin meat area, and the confluence of the products is the thin meat area.

通过本产品的肉厚梯度技术，可以实现以下功能:注塑口少，一般为2~4个喷嘴，所以模具简单，成本相对较低;快速成型可以实现，因为橡胶嘴的远端是一个瘦肉区域，容易实现产品的填充;通过计算等厚度保险杠的重量与等厚度保险杠的重量相差约15%，可以节约注塑材料。

Through the meat thickness gradient technology of the product, the following functions can be realized: less injection ports, generally 2-4 nozzles, so the mold is simple and the cost is relatively low; rapid prototyping can be realized, because the far end of the rubber nozzle is a lean meat area, which is easy to realize the filling of the product; By calculating the difference between the weight of equal thickness bumper and that of equal thickness bumper by about 15%, the injection material can be saved.