硅橡胶热膨胀模具设计与纵横加筋壁板成型质量分析

 采用闭模硅橡胶热膨胀工艺和硅橡胶辅助热压罐工艺,制备了碳纤维复合材料纵横加筋壁板,分析了2种工艺成型过程的特点及其对成型质量的影响。进一步考察了硅橡胶辅助热压罐工艺下工艺间隙、硅橡胶厚度和金属模块定位对制件密实状态和尺寸精度的影响。结果表明:相比闭模热膨胀工艺,所采用的硅橡胶辅助热压罐工艺及其模具方案更适合于成型纵横加筋壁板;热压罐工艺应按照硅橡胶自由膨胀的方式来设计工艺间隙;硅橡胶的厚度对密实质量影响较小,但厚度越大温度不均匀性越明显;热压罐工艺中采用金属模块定位的方法可以明显提高加筋肋交汇处的尺寸精度和密实质量。研究结果对复合材料格栅结构制造质量控制技术的发展具有指导意义。

Thermal Expansion Mold Design Using Silicone Rubber and Processing Quality Analysis of Bidirectional Stiffened Plates

A thermal expansion process with a closed mold and a silicone rubber assisted autoclave process are both adopted to produce bidirectional stiffened carbon fiber reinforced composite plates.The features of these two processes and their effects on the processing qualities are analyzed.Furthermore,for the silicone rubber assisted autoclave process,the effects of process gap,thickness of silicone rubber and metal mold positioning on the consolidation and dimensional accuracy of the products are studied.The results demonstrate that compared with the thermal expansion process with a closed mold,the silicone rubber assisted autoclave process and its mold design are more suitable for the production of bidirectional stiffened composite plates.The process gap of the thermal expansion process should be designed based on the free-expansion mode of the silicone rubber in the autoclave process.Moreover,the thickness of silicone rubber has little effect on consolidation,while larger thickness results in more obvious unevenness of temperature.The method that holds the metal mold in position in the autoclave process can significantly enhance the dimensional accuracy and consolidation degree at the intersection of ribs.These research results are of significance to the development of control technology on the manufacturing quality for composite grid stiffened structures.