织物经纬向对硅橡胶制品成型工艺及力学性能的影响

Effect of Warp and Weft Directions of Fabric on Molding Process and Mechanical Property of Silicone Rubber Products

对比涤纶针织布、涤纶网眼布、玻璃纤维布3种织物及其与硅橡胶复合材料的经纬向性能,分析织物经纬向对硅橡胶制品成型工艺和力学性能的影响。结果表明:3种织物的纬向拉断伸长率均大于经向拉断伸长率;织物/硅橡胶复合材料的力学性能主要由织物提供,纬向拉断伸长率大于经向拉断伸长率,在小变形时经向拉伸力大于纬向拉伸力;加入织物的复合材料的收缩率显著降低,纬向收缩率大于经向收缩率;利用涤纶针织布纬向的大变形,可实现异形制品表面织物无搭接成型;利用织物纬向变形可解决玻璃纤维布/硅橡胶制品长度方向易弯折的问题;增加织物后中空P形结构硅橡胶制品的经向压缩力大于纬向压缩力。在硅橡胶制品结构、模具和工艺设计时,为保证制品的质量一致性,应充分考虑织物经纬向。

The warp and weft direction properties of three fabrics,including knitted polyester fabric,polyester mesh fabric and glass fiber cloth,and their composites with silicone rubber were compared,and the effect of warp and weft direction on the molding process and mechanical properties of silicone rubber products was analyzed.The results showed that,the elongation at break of the three fabrics in the weft direction was greater than that in the warp direction.The mechanical properties of the fabric/silicone rubber composites were mainly provided by fabrics.The elongation at break of the composites in the weft direction was greater than that in the warp direction,and the tensile stress in the warp direction was greater than that in the weft direction at small deformation.The shrinkage of the fabric composites decreased significantly compared with the rubber without fabrics,and the shrinkage in the weft direction was greater than that in the warp direction.The large weft direction deformation of the knitted polyester fabric could be used to realize the non-overlapping molding of the fabric on the surface of special-shaped products.The problem of easy bending in the length direction of the glass fiber cloth/silicone rubber products could be solved by utilizing the weft deformation of the fabric.After adding fabric,the compressive force in the warp direction of the hollow P-shaped silicone rubber products was greater than that in the weft direction.The warp and weft direction properties of the fabric should be fully considered in the structure,mold and process design of silicone rubber products to ensure the quality consistency of the products.