VARTM process of composites using double-bag air cushion method

This article introduced the double-bag air cushion method (DBACM) as an economical and efficient manufacturing process of polymer composites associated with the vacuum-assisted resin transfer molding (VARTM) process. The method utilizes an improved double-bag along with several air cushions to create distribution channels for enhancing the resin flow during infusion. Experimental evaluation on resin infusion behavior and mechanical properties, including ultimate strength, void content, surface finish, and thickness uniformity, is performed for composites reinforced with both jute fibers and glass fibers. Results showed that the DBACM reduces the infusion time by more than 26.0% as compared with traditional VARTM. The difference in ultimate strength of the part between the DBACM and the VARTM is about 2.9%–3.9%. The void content of the E-glass composites is 1.3%–1.5% due to the few fissure-like microvoids, whereas the void content of the jute composites is high, about 2.4%–4.0%, because of the sparse spherical macrovoids. Additionally, there are no major differences in surface finish and thickness uniformity between the parts fabricated by DBACM and by conventional VARTM.