Sintering is a comprehensive process that involves complex evolution of material microstructures and properties, being recognized as a key factor to improve the machinability of ceramics. The present study aims to address the densification mechanisms of 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) based on the properly designed sintering experiments. The impacts of sintering temperature on the grain growth, phase composition, and mechanical properties were rigorously studied. A particular focus is placed on identifying the correlations between the sintering scheme and the machinability of 3Y-TZP by conducting a series of milling tests. The acquired results indicate that the porous zirconia begins to crystallize at 1100 °C and gradually converts to ceramic characteristics after 1200 °C, resulting in a significant increase of cutting forces and temperatures. Moreover, the zirconia sample sintered at 1200 °C exhibits obvious ductile-brittle removal characteristics and moderate hardness. Thus, a precise control of the machined surface quality can be achieved by cutting within the ductile regime.

烧结是一个涉及材料微观结构和性能复杂演变的综合过程，被认为是提高陶瓷可加工性的关键因素。本研究旨在基于适当设计的烧结实验来解决 3 mol% 氧化钇稳定的四方氧化锆多晶 (3Y-TZP) 的致密化机制。严格研究了烧结温度对晶粒生长、相组成和机械性能的影响。通过进行一系列铣削测试，特别关注确定烧结方案与 3Y-TZP 可加工性之间的相关性。所得结果表明，多孔氧化锆在 1100°C 开始结晶，1200°C 后逐渐转变为陶瓷特性，导致切削力和温度显着增加。此外，在 1200 °C 下烧结的氧化锆样品表现出明显的韧脆去除特性和中等硬度。因此，可以通过在延性范围内切割来实现对加工表面质量的精确控制。