Effectiveness of ELID Grinding and Polishing

Grinding Technology for Engineering Ceramics - A Review

“…The ''machining '' approach involved measurement of the grinding forces and specific energy coupled with microscopic observations of the surface morphology and grinding detritus [4]. From the machining approach, it has become evident that material removal for grinding of ceramics occurs mainly by brittle fracture, although most of the grinding energy is associated with ductile flow due to plowing [5]. For example the material removal in the high speed deep grinding of alumina and alumina-titania was dominated by grain dislodgement or lateral cracking along grain boundaries, while the removal for zirconia was via both local micro fracture and ductile cutting [6].…”

“…In contrast, however, the share of grit splintering increases, leading to an increase in the number of single cutting edges. The respective wear mechanisms balance each other, so the wear remains generally almost unaltered [5]. The changed courses of motion and speed during UAG moreover cause different load conditions such as steeper angles of engagement, shorter cutting lengths and higher depths of engagement than during conventional grinding.…”

“…For high-efficiency ELID grinding, a thinner insulating layer on the wheel surface is required. However, for a mirror finish ELID grinding a relatively thick oxide layer is preferred [5].…”

“…The grinding energy required for ductile mode is different from that for brittle mode. Based on the concept of the critical depth-of-cut dc, which has attracted considerable attention so far, a general description has been successfully introduced to express the brittle-ductile relationship [5]. The critical depth dc for fracture initiation is described as follows 2 ( )( )…”