国产T800级航空预浸料固化动力学研究及TTT图绘制

Study on curing kinetics and time-temperature-transition(TTT)diagram of domestic T800 aerospace prepregs

成型工艺的确定是复合材料制件批量化生产的先决条件,材料与工艺是否适配将直接影响复材制件的外观(如表面胶瘤、贫胶等)、外形(如轮廓度、变形等)、孔隙率等,而预浸料的固化动力学研究及TTT图是复合材料预成型、固化成型工艺制订与优化的重要研究方法与参考依据。以国产T800级航空预浸料为主要研究对象,通过差示扫描量热法建立混合固化动力学模型,拟合结果与实验结果相符,拟合系数达0.99;以流变测试结果构建化学流变方程与凝胶方程,结合动力学模型计算该预浸料的平均凝胶固化度为0.375;基于玻璃化温度(Tg)与固化度测试结果形成Di Benedetto拟合方程,结合动力学方程、凝胶方程、流变方程结果,绘制了预浸料的TTT图,并以实际固化工艺过程温度监测结果验证此动力学方程与TTT图的有效性。

The molding process is a prerequisite for the mass production of composite components,and the compatibility between materials and process directly affect the appearance(such as surface defects,voids,etc.),shape(such as contour,deformation,etc.),and porosity of the composite components.The study of the curing kinetics and the TTT diagram of prepregs are important methods and references for the formulation and optimization of composite preforming and curing processes.The article focused on domestic T800 aerospace prepreg,and the hybrid curing kinetics model was established through differential scanning calorimetry(DSC),which matched the experimental results with a fitting coefficient of 0.99.The chemical rheological equation and gelation equation were constructed according to rheological test results,and combined with the kinetic model,the average gelation degree of the prepreg was calculated to be 0.375.Di Benedetto fitting equation was formulated based on the glass transition temperature(T g)and curing degree test results,and the TTT diagram of the prepreg was plotted by combining the kinetic equation,gelation equation,and rheological equation.The effectiveness of this kinetic equation and TTT diagram was validated through temperature monitoring results during the actual curing process.