Effects of abrasive grain size of flexible body-armor-like abrasive tool (BAAT) on high-shear and low-pressure grinding for zirconia ceramics

Zirconia ceramics exhibit remarkable performance. However, the high hardness and brittleness poses enormous challenges for machining. This study is integrally focused on preparing a flexible body-armor-like abrasive tool (BAAT) with enhanced tangential-to-normal force ratio. The rheological characteristics of the BAAT abrasive system with different abrasive grain were investigated. A series of grinding tests were conducted on a precision grinding machine. The grinding performance of the BAAT with different abrasive grain sizes was examined. Surface roughness (Ra) variation and tangential-to-normal force ratio were analyzed, together with the investigation of the three-dimensional surface morphology and surface hydrophilicity. It was found that smaller abrasive grain sizes ultimately generated lower surface roughness values after grinding. Under the optimal grinding conditions, the surface roughness (Ra) of zirconia ceramics decreased from 102 nm to 1.7 nm after 5 grinding strokes (similar to 1 min). Meanwhile, uniform grinding textures were obtained.