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In this study, we examined the improvements in friction and wear properties between steels for aircraft parts, resulting from the surface modifications with electroless plating film and amorphous carbon coating or diamond‐like carbon (DLC) coating. Friction and wear properties are measured using a pin‐on‐flat wear‐testing machine with reciprocating sliding. From measurements of the coefficient of friction and wear amount, observations during sliding motion and visual inspection of wear traces, the following was clarified. A remarkable improvement of friction and wear properties is realized by DLC coating. Electroless plating increased the hardness of the plated surface considerably. However, it does not contribute to improved friction and wear properties.

Electroless plating treatment is one surface modification technique. An added effect due to electroless plating is expected, and the vibration damping capacity of the structures may be improved by this technique. In the present study, the vibration damping capacity of such electroless plated structures is measured experimentally. Damping capacity can be improved regardless of the plated film materials. Improvement efficiency with an electroless plating film with dispersed foreign particles such as SiC ceramics is higher than with a uniform electroless plating film.

This study seeks to clarify the behavior of ground materials and the grinding mechanism corresponding to the wear of abrasives, in the grinding process by coated abrasives.

Cemented carbide ball indenters for abrasive grains were used. Cemented carbide ball indenters have a definite shape. Grinding process is carried out using a wear‐testing machine with a reciprocating motion. This is an abrasive wear test. The deformation of the ground material is observed by the measurement of the worn groove and optical microscopic photograph of the worn ground surfaces.

Grinding process regularly proceeds when indenter diameter is small, that is, abrasive has a good cutting quality. However, when abrasives are gradually worn and the cutting quality becomes worse, a groove formed by grinding process is again filled up by the re‐adhesion of the generated worn debris. So, the grinding process by coated abrasives is impossible.

To clarify the effects of indenter shape and its material on the abrasive wear of the workpiece or grinding process by coated abrasives, the additional experiments are now planned using other indenters having different shape or material in the laboratory.

In this research, interesting phenomena in grinding process by coated abrasives are found. This result is useful for the improvement of coated abrasives.

It is clarified that the grinding process by coated abrasives (that is, the behavior of ground material) can be simulated by this abrasive wear experiment.

Engineering plastics having good mechanical properties are at present frequently used as materials for various machine elements. In this research, experimental investigations have been carried out regarding tribological factors such as friction and wear for five kinds of fundamental engineering plastics: non‐reinforced polycarbonate, polyphenylene oxide, polyamide, polyacetal, and polybutylene terephthalate. It is clarified that the tribological properties, especially the wear properties of the engineering plastics are influenced by the friction conditions and heat transfer characteristics on contact surfaces. However, no clear effects of mechanical strength such as tensile strength or hardness are seen. Thus, the fundamental wear properties of engineering plastics are strongly influenced not only by their own thermal characteristics but also by those of contact surfaces.