碳纤维增强复合材料零件精确固化成型方法

With considering the great demands of aerosapce manufacturing industry, the key design problems of tooling for autoclave curing have been researched to satisfy the large complex composite component processing.The composite tooling lay-up method based on the equal Coefficient of Thermal Expansion(CTE) with composite part has been proposed to achieve an accurate processing of composite part.The CTE of tooling can match with the composite component by choosing the aporopriate tooling material and design the tooling broad lay-up method. Based upon the stress free temperature of composite part, the accurate tooling surface design technology was developed to predict the surface of composite tooling.This technology was researched by analysing the curing process of carbon fiber reinforced composite materials and found out the composite part shape was deteminered by tooling surface when the processing temperature reached the stress free temperature.This kind of technology can solve the tooling design problems caused by traditional design approach which repeatedly modiy the tooling surface based on the warping of composite part.At the same time, the manufacturing efficiency and the quality of composite component is increased. The research achievements can be directly applied in the the manufacturing of large complex composite structures in large passenger aircraft,aerospace products and wind power facilities.

结合航空制造行业的重大实际需求，研究飞机大型复杂复材零件热压罐成型的工装设计难点，提出基于各向热膨胀系数匹配的复材工装模板铺层设计方法，选择合适的复材制作工装模板，通过对工装模板铺层设计实现工装与制件各向热膨胀系数相匹配。提出基于应力临界点温度的工装模板型面精确设计方法，分析碳纤维增强树脂基复材固化工艺曲线，以内应力为零的临界点温度时的工装型面作为零件型面，据此求解工装模板型面，克服了传统方法由零件常温型面直接拷贝生成工装型面，然后根据制件回弹量反复修模的问题，提高了效率和质量。研究成果可直接作为大飞机等新机研发的技术储备，在航天、风电等行业大型复杂复材零件热压罐成型中也具有广阔的应用前景。

本项目针对飞机大型复杂复材零件热压罐成型工装设计难点，深入研究了复合材料工装型面快速精确求解方法。采用低温成型高温使用的LTM16复合材料预浸料制造工装模板，提出了基于工装与复材零件各向热膨胀系数匹配的复材工装模板铺层设计方法。提出了基于应力临界点温度的工装模板型面精确设计方法，深入研究了复材工装与零件在热压罐固化工艺不同阶段的变形，以应力临界点温度时的复材零件型面作为依据，设计室温时的工装模板型面。实验结果表明，上述工装成型的复材零件固化变形量明显低于传统热压罐金属工装成型的复材零件。项目相关研究内容在大型航空企业得到初步应用和验证。研究成果为高性能复材零件在航空航天、轨道交通与新能源等行业的推广应用提供了有效手段。研究团队进一步发现，热压罐固化成型大厚度与变厚度复材零件仍然存在较大变形。本质上是由于复材零件在热压罐固化过程中厚度方向温度梯度大，容易造成应力分布不均。本项目在全面完成预期研究内容和研究目标的基础上，进一步提出了复材微波高压固化技术，为减小大厚度与变厚度复材零件的固化变形提供了新的有意义的尝试和探索。项目实施期间共发表6篇国际SCI期刊论文，1篇核心期刊论文，授权国家发明专利1项，公开1项，培养硕士研究生2名，博士研究生2名。