成型压力对5428VB/T700复合材料微观结构与性能的影响

Influence of Pressure on the Microstructure and Mechanical Properties of 5428VB/T700 Composite

5428VB/T700预浸料适于真空成型高性能复合材料。为了进一步提高该类材料的通用性,本工作采用热压罐法成型5428VB/T700复合材料,研究了加压时机、施加压力大小等对复合材料基本力学性能的影响,采用超声扫描、微观结构分析等对复合材料板材质量进行了分析,并和相应的真空成型5428VB/T700复合材料进行了比较。结果表明,在130℃/1h前施加0.3-0.6MPa的压力,5428VB/T700复合材料的短梁剪切强度相对于真空压力成型体系有较明显降低,但随压力的增大有增加趋势;在130℃/1.5-2.0h施加0.3-0.6MPa压力时,5428VB/T700复合材料的基本力学性能相对于130℃/1h前施加压力的体系有较明显提高,并随压力的增大有增加趋势,当施加的压力达到0.6MPa以上时,复合材料的基本力学性能和质量优于相应的真空压力成型复合材料体系。分析了复合材料成型过程中的气泡运动历程以及孔隙的形成原因等。

5428VB/T700 is a kind of vacuum bag curable prepreg. In order to improve its popularity, autoclave technique was used to manufacture 5428VB/T700 composite laminates. Influence of pressure magnitude, pressure applied time point on the basic mechanical properties of 5428VB/T700 composite had been investigated here, ultrasonic scanning, microstructure analysis techniques were used to inspect the quality of prepared 5428VB/T700 composite laminates, and the properties of vacuum bag only cured 5428VB/T700 laminates were compared to those of autoclave cured 5428VB/TT00 laminates. Results indicated that the short beam shear strength of 5428VB/T700 composite decreased when 0.3-0. 6MPa pressure was applied before 130℃/1h compared to those of vacuum bag cured system, but increased with the increase of applied pressure magnitude. The properties and qualities of 5428VB/T700 composite were improved significantly when 0. 3-0. 6MPa pressure was applied at 130℃/1.5-2. Oh, and when the applied pressure was no less than 0.6MPa, the properties and qualities of 5428VB/T700 composite were better than those of vacuum bag only cured 5428VB/T700 laminates. Process of bubbles removed and the formation of voids in composite laminate were discussed.