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Neutron shielding fibre metal laminates (NSFMLs) containing 10–50 wt% of boron carbide (B 4 C) powder were fabricated using hot molding process, and the effects of experimental temperature on the thermal and mechanical properties of composite laminates were investigated in this work. Thermal stability of composite laminates was conducted with thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC), and their mechanical properties were also measured. The testing results indicated that good interfacial adhesion between different layers, uniform distribution of B 4 C particles and carbon fibres tightly surrounded by polyimide (PI) resin were crucial to the mechanical properties of composite laminates. TGA-DSC results illustrated the scarcely mass loss of composite laminates below 300 °C, yet began to decompose when it exceeded over 390 °C. Moreover, tensile strength of the NSFMLs degraded with the increasing of experimental temperature and the volume fraction of B 4 C powder. Double bear shear (DBS) testing results showed that the NSFMLs with 30 wt% of B 4 C powder had the maximum interlaminar shear value, while the primary delamination zone occurred at the interface between two layered carbon fibre reinforced prepregs (CFRPs). The composite laminates still maintained the good interlaminar shear strength even at 300 °C. [ABSTRACT FROM AUTHOR]

Abstract: The flow behaviors of CLAM steel were investigated to obtain the forming simulation parameters. The hot deformation experiment was performed under the strain rate of 0.001–5s−1 and the temperature of 850–1050°C on Gleeble-1500 thermo-simulation machine. The results showed that the flow stress decreased with the increasing deformation temperature but increased with the increasing strain rate. Moreover, material constants α, n, lnA and activation energy Q were calculated as a function of strain. Constitutive equation of Arrhenius-type allowing for the effects of strain, strain rate and temperature was developed to describe the hot deformation behaviors of CLAM steel. The flow stress of CLAM steel predicted by the proposed constitutive equation highly coincided with the experimental results, which demonstrated that the developed constitutive equation could precisely predict the flow behaviors of CLAM steel. [Copyright &y& Elsevier]