Surface formation and grinding response in TTG-based micro-grinding

Micro-grinding has emerged as a promising technology for the precision fabrication of micro-structured surfaces on advanced materials. This study systematically investigates the micro-grinding characteristics of ceramic micro-grooves using a Twin-Turret Generator (TTG) machine tool with cylindrical coordinate architecture. Taguchi experiments were conducted to evaluate the effects of spindle speed, feed rate, and grinding depth on surface roughness, grinding force, and edge material pile-up. Statistical analyses, including analysis of variance (ANOVA), correlation analysis, and Grey Relational Analysis (GRA), were performed to evaluate the individual and comprehensive machining responses. Furthermore, a stochastic undeformed chip thickness model incorporating the random distribution of abrasive grains was established to interpret the material removal mechanism. The results indicate that feed rate and grinding depth are the dominant parameters governing grinding force, surface integrity, and edge quality, whereas spindle speed exhibits a comparatively weaker influence within the investigated range. The proposed undeformed chip thickness model successfully explains the observed variations under different grinding conditions. The optimized processing parameters provide a practical reference for achieving high-quality micro-grooves. This work demonstrates the feasibility of TTG-based micro-grinding for precision fabrication of ceramic micro-structures and provides theoretical and experimental guidance for micro-grinding on cylindrical-coordinate machine tools.