Mechanical wear of different crystallographic orientations for single abrasive diamond scratching on Ta12W

• Wear processes are obviously different with different crystallographic orientations.
• The SCD100 grit has a much longer scratching life than the SCD111 grit.
• Major frequencies of AE signals are similar for the two types of SCD grits.
• Different stress and crystallographic orientations result in different wear modes.

Mechanical wear is one of the dominant modes in abrasive machining. Single crystal diamond (SCD) mechanical wear characteristics with different crystallographic orientations (SCD100 and SCD111) during scratching on Ta12W were systematically investigated. The wear mechanism involved in the scratching was explored. The scanning electron microscope examination of the worn SCD and the analysis of the wear volume, scratching force and acoustic emission signals involved in the scratching process indicated that the mechanical wear progression of two SCD grits is obviously different. A standard scratch tester experiment with a conical indenter was also carried out. It was found that the scratching force ratio for a SCD100 grit was similar with the friction coefficient in the standard scratch tester, which was higher than the case for a SCD111 grit. The wear resistance of the SCD111 grit is greater than the SCD100 grit in a normal wear situation. However, the SCD100 grit has a much longer scratching life than the SCD111 grit. Different stress and crystallographic orientations result in different cleavage fracture modes.