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The degradation of components resulted from wear is unavoidable in service, which could be partly solved by applying surface treatment technique. Stellite-6 cobalt-based alloy is considered as a potential cladding material to improve the wear resistance of base materials owing to its excellent hardness and strength. The microstructural evolution and local mechanical properties of Co-rich matrix and Cr-rich eutectic carbide of Stellite-6 cladding with different aging times at 900 °C are investigated by optical microscopy, field emission scanning electron microscope and nanoindentation testing. The tribological characteristics of the matrix and eutectic carbide itself are systematically investigated using the single-pass nano-scratch testing. In the matrix region, the carbide precipitations occur after 5 h and coarsens after 10 h aging. The nanoindentation results indicate that the hardness of the matrix regions is significantly increased due to the presence of dispersed carbide and fine stripe-like precipitations. The nano-scratch tests depict that the wear resistance is improved with higher matrix hardness to support eutectic carbide based on aging treatment. Potential improvement on tribological performance through the aging treatment procedure is proved based on the micromechanical and wear behaviors of matrix and eutectic carbide were identified. [ABSTRACT FROM AUTHOR]

As a nontraditional processing technology, electrochemical discharge machining (ECDM) can process glass and engineering ceramics precisely. This technology has proven to be a potential process for glass 3D microstructure. However, the key to expanding the application of ECDM is how to improve machining accuracy. This research conducted micro-hole and microgroove machining. Power voltage and frequency influence on hole processing efficiency, hole entrance diameter, and hole limit depth was explored. We considered four factors affecting ECDM—the voltage and frequency of the pulse power supply, the tool electrode feed rate, and the rotation speed. We studied their influence on the roughness of the microgrooves. The results show that machining efficiency, entrance diameter, and limit depth of micro-holes increased with the increase in voltage but decreased with the increase in power frequency. The results show that the roughness of microgrooves has an apparent positive correlation with the power voltage. In contrast, it had an evident negative correlation with the power frequency and electrode speed. The bottom surface roughness of microgrooves can be as minor as 0.605 μm. Various complex 3D microstructures on the glass surface by layer-by-layer method proved the great potential of ECDM. [ABSTRACT FROM AUTHOR]