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The study of the rheology of injected or compression moulded compounds like SMC or BMC is made particularly difficult by the high content and the intricate arrangement of their fibrous reinforcement. For these two types of compounds, inappropriate rheological testing protocols and rheometers are often used, which leads to a very large scatter of the experimental data. This study describes specific sampling and specimen’s preparation methods, as well as dedicated rheometry devices to test their rheology. Following the proposed protocols, it is possible to obtain rheological measurements showing low scatter of the recorded stress values: about ±10% for SMC and about ±15% for BMC-like compounds.

Due to the complexity of micro-damage and boundary conditions in complex stress state, most micro-mechanical analyses of continuous SiC fiber-reinforced titanium matrix (SiC/Ti) composite mainly focus on in-plane stress state, which have not taken out-of-plane loadings into consideration. In this paper, a three-dimensional finite element model (FEM) has been developed to realize micro-mechanical analysis of SiC/Ti composite under complex stress state. The model is composed of a representative volume element (RVE). The effects of matrix plasticity, interface debonding and residual thermal stress are considered. The unified periodic boundary conditions and mixed-mode damage evolution law of the interface were adopted to make the RVE applicable in complex stress state. Single fiber push-out tests were carried out to estimate the interfacial shear strength. Good agreement between the simulation results and experiment data of uniaxial tension proved the model validity. The simulation results indicate that out-of-plane loadings have great influence on mechanical property degradation of SiC/Ti6Al4V composite. Besides, the interface debonding areas and matrix plasticity regions are no longer bilateral symmetrical under the effect of transverse shear load.

Use of thermoplastic composite material for load bearing components is increasing due to economical processing of complicated shapes in large quantities. Addition of fibre improves the strength and modulus of composites. Although the tribo-behaviour of thermoplastic composites were investigated, the friction and wear mechanisms are not yet fully understood. Friction and wear behaviour of injection unfilled Nylon 66, glass fibre reinforced Nylon 66 and carbon fibre reinforced Nylon 66 is investigated under dry sliding conditions. Tests were conducted at different normal loads and sliding velocities at room temperature. Coefficient of friction, wear loss and heat generation during the wear tests were quantified. Presence of fibre affects coefficient of friction and wear resistance of Nylon 66 matrix composites. The formation and stability of the transfer films affects the wear resistance. The rise in temperature during sliding was also calculated and also measured. The contact temperature rise is influenced by the composition which in turn influences the fibre adhesion and thereby the wear resistance. Glass fibre reinforced Nylon exhibited the lowest wear rate among the materials investigated. Both adhesive and abrasive wear mechanisms were observed in polymer matrix composites.

The paper presents a novel kind of carbon foam composites reinforced by chopped glass fibers. Microstructure, mechanical properties and thermal insulation of the composites have been investigated by scanning electron microscopy, universal testing machine and laser thermal constant analyzer, respectively. Results showed that carbon foam composites had a spherical and closed-cell structure; chopped glass fibers were uniformly distributed in the carbon matrix along different directions. The mechanical properties exhibited optimum with the 7% glass fiber additives, 11.27 MPa of shear strength, higher than that of pure carbon foams by as much as 111%. Compressive and shear fracture were both characterized by gradient brittleness. Many tiny open-pores existed in carbon foams with a certain amount of glass fiber additives, giving rise to the higher thermal conductivity. Nevertheless, carbon foam composites possessed good thermal insulation, 0.311 W·m−1·K−1 at room temperature, and 1.04 W·m−1·K−1 in 800 °C at the most.

In this work, the stress analysis of isotropic and ortotropic laminae both with a hole and without a hole and laminated both with a hole and without a hole composite plates have been examined using the finite element method. In order to solve the problem, a computer program has been written by using characteristics of eight-node isoparametric plane element. The calculations have been tested on various composite and steel materials by this program. The results have been shown in diagrams and tables and compared with literature. It was observed that the stress distributions in the plate with a hole was totally different from the plate without a hole. The analyses have showed that, the elastic stresses have been gradually reduced as moving from the first layer to the second.

The damages of 3D orthogonal woven composite circular plate under quasi-static indentation and transverse impact were tested with Materials Test System (MTS) and modified split Hopkinson bar (SHPB) apparatus. The load vs. displacement curves during quasi-static penetration and impact were obtained to study the energy absorption of the composite plate. The fluctuation of the impact stress waves has been unveiled. Differences of the load-displacement curves between the quasi-static and impact loading are discussed. This work also aims at establishing a unit-cell model to analyze the damage of composites. A user material subroutine which named VUMAT for characterizing the constitutive relationship of the 3-D orthogonal woven composite and the damage evolution is incorporated with a finite element code ABAQUS/Explicit to simulate the impact damage process of the composite plates. From the comparison of the load-displacement curves and energy absorption curves of the composite plate between experimental and FEM simulation, it is shown that the unit-cell model of the 3D woven composite and the VUMAT combined with the ABAQUS/Explicit can calculate the impact responses of the circular plate precisely. Furthermore, the model can also be extended to simulate the impact behavior of the 3D woven composite structures.

The mechanical and microstructural properties of 6061+20% Al2O3p and 7005+10% Al2O3p aluminium based metal matrix composites joined by friction stir welding were analyzed in the present study. The two materials were welded into the form of sheets of 7 mm thickness after T6 treatment and were tested in tension at room temperature. The microstructure of the joints was observed by optical microscopy and the fracture surfaces were analyzed by employing a scanning electron microscope equipped with field emission gun in order to study the micromechanisms involved during the deformation.