Linglin Zhang

Bio: Linglin Zhang is an academic researcher from Nanjing University of Aeronautics and Astronautics. The author has contributed to research in topics: Curing (chemistry) & Composite number. The author has an hindex of 2, co-authored 2 publications receiving 17 citations.

Indirect Microwave Curing Process Design for Manufacturing Thick Multidirectional Carbon Fiber Reinforced Thermoset Composite Materials

Abstract: Recently, indirect microwave curing technology was developed to process multidirectional carbon fiber reinforced composite materials with high efficient and energy saving purpose. The aim of this paper is to solve the problem of large mid-plane heat generation in manufacturing this kind of materials with large thickness. The difference between the traditional thermal curing and indirect microwave curing processes was analyzed. A Multiphysics model was constructed to reflect the composite curing behavior in a cost-effective manner, which agreed well with the experimental results. On this basis, a new indirect microwave curing cycle was designed, and relevant process parameters were determined. Compared with the manufacturer’s recommended cycle, the degree of mid-plane heat generation was greatly relieved, and a reduction of 34.6% in composite residual strains was achieved. Moreover, the curing cycle was reduced by 38%, while the interlaminar shear strength of the composite was improved by 1.38 times. Corresponding reinforcement mechanisms were explored through the observation of composite cross-sections with optical microscopes.

Anisotropic Dielectric Properties of Carbon Fiber Reinforced Polymer Composites during Microwave Curing

Abstract: Microwave cuing technology is a promising alternative to conventional autoclave curing technology in high efficient and energy saving processing of polymer composites. Dielectric properties of composites are key parameters related to the energy conversion efficiency during the microwave curing process. However, existing methods of dielectric measurement cannot be applied to the microwave curing process. This paper presented an offline test method to solve this problem. Firstly, a kinetics model of the polymer composites under microwave curing was established based on differential scanning calorimetry to describe the whole curing process. Then several specially designed samples of different feature cure degrees were prepared and used to reflect the dielectric properties of the composite during microwave curing. It was demonstrated to be a feasible plan for both test accuracy and efficiency through extensive experimental research. Based on this method, the anisotropic complex permittivity of a carbon fiber/epoxy composite during microwave curing was accurately determined. Statistical results indicated that both the dielectric constant and dielectric loss of the composite increased at the initial curing stage, peaked at the maximum reaction rate point and decreased finally during the microwave curing process. Corresponding mechanism has also been systematically investigated in this work.

Multifunctionality in Epoxy Resins

Abstract: Epoxy resin will continue to be in the forefront of many thermoset applications due to its versatile properties. However, with advancement in manufacturing, changing societal outlook for the chemic...

Surface-modified alumina nanoparticles-filled aramid fiber-reinforced epoxy nanocomposites: preparation and mechanical properties

Abstract: Surface of Al2O3 nanoparticles was modified with a silane coupling agent, and aramid fiber-reinforced epoxy nanocomposites were produced using these particles. Three different types of laminated nanocomposites were produced. These nanocomposites were obtained by adding modified nanoparticles to the epoxy resin and the aramid fiber, each separately, and to both epoxy resin and aramid fiber. All nanocomposites were produced by vacuum-assisted resin infusion method. The surface-modified Al2O3 nanoparticles were used in five different weight ratios (1, 2, 3, 4 and 5%) according to the epoxy resin. Tensile, three-point bending and Charpy impact tests were performed. Moreover, SEM images were analyzed, and EDX analysis was performed to confirm the elements inside the nanocomposites. As a result, it was shown that the flexural strength and Charpy impact energy of aramid fiber-reinforced epoxy nanocomposites were increased. Finally, a statistical analysis was performed using one-way ANOVA method to show that the results obtained experimentally were statistically reasonable.

Indirect Microwave Curing Process Design for Manufacturing Thick Multidirectional Carbon Fiber Reinforced Thermoset Composite Materials

Abstract: Recently, indirect microwave curing technology was developed to process multidirectional carbon fiber reinforced composite materials with high efficient and energy saving purpose. The aim of this paper is to solve the problem of large mid-plane heat generation in manufacturing this kind of materials with large thickness. The difference between the traditional thermal curing and indirect microwave curing processes was analyzed. A Multiphysics model was constructed to reflect the composite curing behavior in a cost-effective manner, which agreed well with the experimental results. On this basis, a new indirect microwave curing cycle was designed, and relevant process parameters were determined. Compared with the manufacturer’s recommended cycle, the degree of mid-plane heat generation was greatly relieved, and a reduction of 34.6% in composite residual strains was achieved. Moreover, the curing cycle was reduced by 38%, while the interlaminar shear strength of the composite was improved by 1.38 times. Corresponding reinforcement mechanisms were explored through the observation of composite cross-sections with optical microscopes.

Microwave processing of carbon fibre polymer composites: a review:

Abstract: Microwave processing of carbon fibre-reinforced polymer (CFRP) composites is gaining increasing attention as an alternative to conventional thermal processing techniques. It has the potential to re...

Polyimide fabric-reinforced polyimide matrix composites with excellent thermal, mechanical, and dielectric properties:

Abstract: Two types of thermosetting polyimide (PI) resin were prepared using a polymerization monomeric reactant method, and high performance PI fabric/PI resin composites were fabricated through a wet infi