Prediction of the Surface Roughness in Ultrasonic Vibration-Assisted Grinding of Dental Zirconia Ceramics Based on a Single-Diamond Grit Model

Abstract

Ultrasonic vibration-assisted grinding (UVAG) is regarded as a superior method for the fabrication of ceramic dentures, due to its outstanding performance in hard and brittle materials’ machining. The surface roughness of dentures has a critical effect on the bonding and wear performance between dentures and natural teeth. Accomplishing the prediction of surface roughness will promote the application of UVAG in dental restoration significantly. However, the investigation about surface roughness modeling in the UVAG of ceramics is limited. In this study, a comprehensive surface roughness model was proposed with the consideration of the diamond grits’ random distribution, brittle fracture removal, and ultrasonic vibration characteristics. Based on the indentation fracture removal mechanism, the material removal process was modeled. Rayleigh’s probability density function was introduced to characterize the random distribution of the grits. Besides, the ultrasonic vibration was considered via the analysis of the single-diamond grit motion. Finally, the comprehensive model was developed with the consideration of all the diamond grits. Afterward, the verification experiments were carried out. The experimental results agreed well with the model predictions. Therefore, the comprehensive model can be applied to evaluate the surface roughness and can provide an in-depth understanding of the surface formation in the UVAG of ceramics.

Study on the Algorithm of Three-Dimensional Surface Residual Material Height of Nano-ZrO2 Ceramics under Ultra-Precision Grinding

“…With the improvement in the measurement precision of ultraprecision machined surface, the three-dimensional roughness has been widely used in the quality evaluation of ultra-precision machined surfaces. Xiao et al [5] established a two-dimensional surface roughness prediction model based on the random distribution of abrasive particles, which provided a new way for the quality evaluation of ceramic surfaces since the three-dimensional roughness is sampled based on a limited number of points in the surface area, which can reflect the surface characteristics of parts more accurately and comprehensively [6,7]. Additionally, the height of each sampling point is closely related to the height of surface residual materials in the sampling area, which makes the height of surface residual materials in the sampling area become a key index in predicting the threedimensional roughness.…”