低压片状模塑料纤维的取向

低压片状模塑料(LPMC)模压流动成型后玻纤在平面内发生取向,导致模压件呈各向异性。文中从成型后制品上取样烧尽树脂,由扫描仪获取纤维数值图像,用Photoshop软件将图像反相、增强,再利用MATLAB软件确定纤维取向分布。并讨论了纤维取向的影响因素、控制方法及对复合材料力学性能的影响。研究表明,LPMC片材的黏度、加料面积及闭模速度是影响制品纤维分布的主要因素,增大片材黏度、增大加料面积及适当提高闭模速度都可以提高制品纤维分布的均匀性。LPMC制品的弯曲强度几乎不随试样的取样位置不同而改变,但在纤维平行取向方向上具有比垂直取向方向上更高的强度和模量。

The Fiber Orientation in Low Pressure Sheet Molding Compounds

The specimens cut from the molded LPMC plates were burned off the resin in an oven for 3h.The fiber images were taken using a scanner and the photo-shop software was used to revert and enhance the pictures and get rid of the backgrounds to make the fibers more obvious to be dealt with.The fiber orientation distribution was analyzed using the MAT-LAB software.At the same time,the effecting parameters and controlling methods on fiber orientation and its effects on the mechanic property of molded parts were studied.Results show that increasing the viscosity of LPMC,augmenting the feeding areas and accelerating the velocity of shut-mold can improve the uniformity of fiber distribution.The flexural strength and flexural modulus paralleled the fiber direction are much higher than vertical one.