Papers by Keyword: ZTA Ceramics

Abstract: The aim of this research is to investigate the combined effects of CeO₂ additions and hot-isostatic pressing sintering (HIPping) technique on the densification of ZTA ceramics. Addition of CeO₂ to ZTA ceramics leads to formation of a secondary phase (CeAl₁₁O₁₈) which played a vital role in affecting the density and porosity. Microstructure investigations showed that HIPping had a significant role in the removal of pores. The sample with 5 wt.% of CeO₂ addition showed the optimum value. The highest bulk density is 4.46 g/cm³ and the lowest percentage of porosity is 0.35%.

Abstract: The nonlocal theory was introduced to establish the nonlocal constitutive model and analyze the effect of ultrasonic on the tensile strength and fracture surface microstructure. ZTA ceramics tensile fracture experimental results show that the tensile stress obviously reduces and the fracture changes under ultrasonic vibration. The experimental results are coincided with theoretical analyses.

Abstract: ZTA ceramics is a kind of high performance structural ceramics, and its surface/subsurface damages after machining have great effect on reliability and long-service life of ceramic parts, so it introduces two-dimensional ultrasonic vibration assisted grinding (TUVAG) which is applied in the precision finishing of ZTA ceramic, mathematic motion model of abrasive grain during TUVAG is established, and the special machining path of abrasive grain during TUVAG is analyzed, and the surface/subsurface damages of ZTA ceramics after TUVAG are further discussed. Experimental results prove that TUVAG may make materials removed in a plastic state mostly, the probability of cracks formation and propagation becomes less, and obviously reduce surface damages of ZTA ceramics, and the grinding badness layer of ceramics after TUVAG is shallower than that after diamond grinding at the same grinding parameters.