The commonly selected material is modified polypropylene (PP), which is roughly composed of PP (about 60%), #p# rubber (cross-linking) about 30%, filler (talc powder) about 9%, and additives (antioxidants, preservatives, nucleating agents and anti ultraviolet agents, etc.) 1%. The material has low temperature impact resistance (Izod impact strength is 6.0kg.cm/cm at - 30 ℃), high fluidity and high coating adhesion (corresponding to E-10).

另外，该材料的外观品质好，能够满足熔合纹细、表面张力好以及A级面无熔合纹等要求。材料可循环使用，并可进行100%回收。

In addition, the material has good appearance quality and can meet the requirements of fine fusion grain, good surface tension and no fusion grain on class a surface. The material can be recycled and 100% recycled.

产品设计

product design

在产品设计阶段，使用MOLDFLOW软件对设计进行CAE分析，以进行生产技术性检证。该分析包括：进胶点位置、进胶点尺寸、产品重量、锁模力、产品填充模拟、流动前沿温度、充填压力、剪切应力、收缩率、困气位置、熔接线、翘曲量、冷却液温度以及制件高温度等。通过CAE分析，可以在设计阶段对产品的不良情况进行调整预防，保证产品成型的顺利进行。

In the product design stage, CAE analysis of the design is carried out by using Moldflow software for production technical verification. The analysis includes: glue inlet position, glue inlet size, product weight, mold locking force, product filling simulation, flow front temperature, filling pressure, shear stress, shrinkage, gas trap position, fusion line, warpage, coolant temperature and high temperature of parts. Through CAE analysis, the bad conditions of products can be adjusted and prevented in the design stage to ensure the smooth progress of product molding.

值得一提的是，保险杠不是“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2.6~3.4mm。大致的原则为：中间属于厚肉区，胶口远端为薄肉区，产品合流部分为薄肉区。

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

通过产品肉厚渐变技术，可以实现以下作用：注塑胶口较少，一般为2~4水口，这样模具简单，造价成本相对较低；可以实现快速成型，由于胶口远端为薄肉区，容易实现产品填充；可以节省注塑材料，通过计算，等肉厚的保险杠和肉厚渐变的保险杠重量相差约15%。

Through the product thickness gradient technology, the following functions can be realized: there are fewer injection rubber ports, generally 2 ~ 4 nozzles, so the mold is simple and the cost is relatively low; Rapid prototyping can be realized. Because the distal end of the rubber mouth is a thin meat area, it is easy to fill the product; The injection molding material can be saved. Through calculation, the weight difference between the bumper with equal meat thickness and the bumper with gradual meat thickness is about 15%.