预复合热塑性聚氨酯碳纤维束熔融涂覆工艺研究

针对复合材料柔性导向三维织造成形工艺,进行了预复合树脂碳纤维束柔性导向线熔融涂覆工艺研究。选用具有良好柔韧性的热塑性聚氨酯作为树脂材料,4束T300-3k碳纤维束合股作为增强材料,研究了预复合碳纤维树脂线密度随温度和纤维牵引速度的变化规律。研究表明,低速情况下预复合树脂碳纤维束线密度基本不变,孔隙率在205℃以后小于20%且随温度变化很小;当速度提高到临界牵引速度后,预复合树脂纤维束线密度开始下降,但在一定速度范围内预复合的树脂流量变化很小;临界牵引速度随温度升高而增加,但在210℃以后基本稳定在1.9 m/min。因此优化的预复合聚氨酯碳纤维工艺参数是树脂熔融温度在210~220℃,纤维牵引速度在1.9 m/min。

Study on Melt Coating Process of Pre-composite Thermoplastic Polyurethane Carbon Fiber Bundles

Aiming at the flexible guiding three-dimensional weaving forming process of composite materials,the melt coating process of pre-composite resin carbon fiber bundle flexible guide wire was studied.The thermoplastic polyurethane with good flexibility was used as the resin material,and the bundle of 3k carbon fiber bundles was used as the reinforcing material.The variation of linear density of pre-composite carbon fiber resin with temperature and fiber traction speed was studied.The results show that the linear density of the pre-composite resin carbon fiber bundle is basically unchanged at low speed,the porosity is less than 20%after 205℃and changes little with temperature.When the speed is increased to the critical transformation speed,the pre-composite resin fiber bundle linear density begins.The decrease,but the flow rate of the pre-composite resin in a certain speed range is small.The critical transition speed increases with the increase of temperature,but is basically stable at 1.9 m/min after 210℃.Therefore,the optimized pre-composite polyurethane carbon fiber process parameters are resin melting temperature of 210-220℃and fiber drawing speed of 1.9 m/min.