Comparison between the mechanical properties of carbon/epoxy laminates manufactured by autoclave and pressurized prepreg

Abstract

An experimental study on mechanical properties, such as strength, elastic modulus and interlaminar fracture toughness of two different manufacturing processes namely autoclave vacuum bagging (AP) and resin liquid Pressurized Prepreg (PP) is outlined in this article. AP is a technique employed to create mechanical pressure on a laminate during its cure cycle. This process have for years enabled aerospace industry to maximize the physical properties of advanced composite materials. The resin liquid PP is an out‐of‐autoclave process in which prepregs are laid up onto a closed‐mold, liquid resin is injected to pressurize the laminate in order to exert the hydrostatic pressure required to consolidate the preform and eliminate any gas bubbles that may form during the setting of the resin and the cure is performed into a heated press. The experimental results indicated that laminates manufactured by the PP process exhibited an overall inferior mechanical performance when compared with the laminates obtained using the AP process. The reduction in the mechanical properties may be explained by the non‐homogeneous resin perculation, interfacial mixing of two types of resins, higher thickness and, consequently, higher resin content of the PP laminates. POLYM. COMPOS., 39:E2562–E2572, 2018. © 2018 Society of Plastics Engineers