Properties Improvement Of Tungsten Alloy Based On Plasma Facing Material By Y₂O₃ And TiC

Energy from hydrogen isotopes of modern nuclear fusion reactor and tritium fusion reaction,and the selection of materials in the reactor has been a nuclear fusion reactor application and development of a challenge,especially for plasma facing materials PFMs?Plasma Facing Materials?,because of its extremely severe service environment,can choose a good service of PFMs is vital for the application of fusion success.W and its alloys have many unique advantages when used as core materials of fusion reactor due to their excellent properties.W has the advantages of high thermal conductivity,high melting point and low sputtering rate,so it is the preferred material for fusion reactor internal plasma facing material?PFM?.However,the low temperature brittleness,recrystallization brittleness and irradiation brittleness of W affect its practical application.Therefore,the dispersion strengthening method of oxide and carbide is chosen to improve its performance.The presence of dispersion particles such as oxides?Y₂O₃,La₂O₃?or carbide?TiC,Zr C,Hf C,Ta₂C?helps to improve the mechanical properties of W and refine grains,thus inhibiting brittleness.In this paper,we study three types of dispersion strengthening W:W-Y₂O₃and W-TiC and W-TiC-Y₂O₃.The material was prepared by wet chemistry and spark plasma sintering.Microstructure is the focus of this paper.The density,size,distribution,crystal structure and interface with matrix of dispersion particles were studied.Characterization techniques are applied through a range of high-resolution characterization techniques,including scanning electron microscopy?SEM?,transmission electron microscopy?TEM?,and energy spectroscopy?EDS?.The experiment is mainly divided into two parts:?1?The vickers hardness and relative density of W-Y₂O₃and W-TiC and W-TiC-Y₂O₃three dispersion strengthening W materials were measured.Compared with pure W,the hardness of dispersion strengthening W material was greatly improved,among which W-Y₂O₃had the highest vickers hardness,which was due to the refinement of Y₂O₃grains,which increased the strength of the material.?2?The microstructure of W-Y₂O₃,W-TiC and W-TiC-Y₂O₃were characterized,and the information of grain shape and size,as well as the shape,size and distribution of dispersion particles in W material were obtained.The second phase particles in the three dispersion reinforced composites are uniformly distributed,and the results of metallography,SEM and TEM all well illustrate the effect of Y₂O₃and TiC on refining grain and increasing toughness and strength of W.