Experimental Study On Indentation Response Of 3Y-TZP

Zirconia?ZrO₂?ceramics is a new type of ceramics with excellent mechanical properties.It has not only high hardness,excellent wear resistance and stability,but also chemical corrosion resistance and electrical conductivity.In order to make better use of this kind of ceramics,people began to try to add different additives to zirconia.Among them,yttrium stabilized tetragonal polycrystalline zirconia?3Y-TZP?obtained by adding 3mol%yttrium oxide?Y₂O₃?oxidant is one of the research focuses.This kind of material has good mechanical properties at room temperature and high temperature,but in the study of material micro-mechanical properties,predecessors are mostly.The analysis of lattice structure and composition of materials is very convenient and intuitive.At the same time,the indentation test of high temperature ceramics at extreme temperature is very few.Therefore,the study of microstructure test and high temperature nanoindentation test analysis is carried out to explore its excellent mechanics.The intrinsic cause of performance.Firstly,the development status of nanoindentation technology for measuring mechanical properties of ceramics at home and abroad is analyzed,and other mechanical testing methods are briefly introduced.Then,it is clear that nanoindentation technology is used to study the Micro-Mechanical Properties of 3Y-TZP.Next,the detailed route of toughening mechanism of zirconia ceramics with different Y₂O₃additives was explored,and the fracture toughness of ZrO₂ ceramics was studied by indentation method.The indentation test of Zwick ZHU2.5 was carried out and the repeatability test of mechanical properties of materials at room temperature was carried out.The fracture toughness of three groups of samples with different Y₂O₃ content and two factors of load were analyzed by experiment.The fracture toughness of materials was calculated by corresponding analysis method.By comparison,it was found that the fracture toughness of ZrO₂ ceramics containing 3mol%Y₂O₃was the best,supplemented by X-ray diffraction.The phase analysis of three groups of specimens by X-ray diffraction?XRD?further confirmed the advantages of the 3Y-TZP material.Micro-nanoindentation technology is a convenient,high-resolution and nearly non-destructive measurement method.Meanwhile,Oliver-Pharr's indentation data theory is used for reference,and a high-temperature nanometer made in laboratory is proposed.The indentation curve of 3Y-TZP was tested by indentation device,and the influence of high temperature environment on the mechanical properties of 3Y-TZP was analyzed by different temperature gradients.The results showed that the hardness and elastic modulus of 3Y-TZP decreased with the increase of temperature.Finally,ABAQUS simulation software is used to analyze the basic mechanical behavior of materials under the above experimental parameters,observe the stress nephogram of materials under nanoindentation,study the stress distribution nephogram of materials under indentation load,compare the load-displacement curves of indentation simulation at different temperatures,and compare with the experimental results,find the load-displacement.The loading part of the curve does not correspond to each other completely.This is due to the environmental factors in the actual experiment process.The results of the simulation analysis are consistent with the experimental results on the whole.On the basis of the above,the composition of 3Y-TZP was determined and analyzed,and the cracks were measured,and the effect of yttrium oxide content on zirconia ceramics was quantitatively analyzed.Thereafter,the mechanical response of 3Y-TZP under high temperature was investigated by mechanical-thermal coupling experiment.The residual indentation morphology of 3Y-TZP after high temperature indentation experiment was observed subsequently,and the influence of high temperature environment on the mechanical response of 3Y-TZP was analyzed.