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This study investigates the influence of temperature and load on the dry sliding property of interface between brake friction material with low metallic formulation and gray cast iron disc. Full factorial design was employed to conduct pin-on-disc wear tests to attain wear and friction response under external heating temperature and applied load ranging from 25-175°C and 50-500N(0.35-3.5MPa), respectively. The analysis of experiment results shows the effect of load on wear rate is almost linear. Wear rate exhibits an increase followed by decrease trend with applied load. Friction coefficient is positively affected by external heating temperature but almost independent of applied load. Quadratic regression is conducted to fit the influence of temperature and load on wear rate and friction coefficient and the result shows sound fitting effect.

An in-plane shear specimen made of dual phase steel designed for ductile fracture studies is presented and then analyzed experimentally and numerically. In the experiment, digital image correlation (DIC) technique is utilized to measure the deformation of the specimen. Based on the implicit nonlinear FE solver Abaqus/Standard, numerical analysis of the specimen is performed by using plane stress and solid elements respectively. The elongation of the specimen's gauge length and the shear strain distribution within the shear zone are compared between the experimental and numerical results and a general good agreement is obtained. Thereafter, based on calculated results, the stress state of the shear zone is investigated in detail. It is shown that the shear stress is dominant within the shear zone despite of the emergence of normal stresses. The deformation is concentrated in the shear zone, where the incipient fracture is most likely to occur. The stress triaxiality and the Lode parameter at the fracture initiation are found to be maintained at a relatively low level, which implies that the stress state achieved by the specimen is close to pure shear. The present study demonstrates that the proposed in-plane shear specimen is suitable for investigation of the fracture behavior of high strength materials under shear stress states.

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