Ti-doped amorphous carbon (a-C) films have been prepared on silicon substrates by DC magnetron sputtering. The adhesive strength of the a-C film and Ti-doped a-C films were measured by scratch tests. The Ti-doped a-C films prepared at 250°C had almost constant values of critical load in the scratch tests irrespective of the Ti concentration. The adhesion of Ti-doped a-C film with high Ti concentration was markedly improved by heat treatment in a vacuum, and the critical loads of the films containing 15 at.% Ti increased from 180 mN to 400 mN. Furthermore, the critical loads of the Ti-doped a-C films increased with increasing deposition temperature. The heat-treated Ti-doped a-C films deposited at 350°C had the maximum critical load of 500 mN. The apparent increase in critical load is caused by the chemical interaction between Ti and the substrate material.

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Dressing is frequently carried out in dry grinding of hard carbon because of loading over short grinding times. However, even if abrasive grains covered with loading chips on a wheel surface still have sharp cutting edges, they are removed with loaded chips by dressing. In this study, we propose the dressless restoration of grindactivity in which loaded chips are removed by peeling off the adhesive tape from the loaded wheel surface after pressing. The process of removing loaded chips in dressless restoration was clarified, and the effects of adhesive tape pressing load and peeling speed on removal characteristics of loaded chips were investigated.

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The effects of sputtering gases on the preparation of boron nitride films using RF sputtering were investigated. Mixtures of Ar-N₂ and Ar-NH₃ were used as reactive sputtering gases. SEM observation indicated the surface morphologies of the sputtered films to be smooth. BN bonding was confirmed in XPS spectra of samples sputtered using Ar-N₂ and Ar-NH₃ mixtures as sputtering gases. The hardness of the film was increased and the friction coefficient was decreased for the Si substrate with increasing N₂ ratio in Ar-N₂ sputtering gas. Relatively high hardness could be obtained with a not-so-slow deposition rate using Ar-NH₃ sputtering gas. Moreover preparation of the BN film on CVD diamond substrates could be performed using this method.

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Nanoindentation and single-point fly cutting (SPFC) were conducted using quartz glass to clarify the elastic and plastic behavior of optical glass in ductile-regime machining using fixed abrasives. From the nanoindentations, the relationships between indentation depth and elastic deformation ratio or plastic deformation ratio were shown to depend on the indenter shape. Three different cutting tools, i.e., a V-shaped diamond cutting tool, a Vickers indenter, and a spherical indenter, were applied to SPFC. The results indicated that the performance of the material removal process, elastic recovery, elastic residual depth of cut and pile-up are dependent on the rake angle and the tip shape of the cutting edges.

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