The Influences Of Y₂O₃ Addition To The Microstructure And Properties Of A Ni-based Superalloy

In order to enhance the mechanic properties of a Ni-based superalloy already in use, we add Y₂O₃ particles to make oxide dispersion strengthen. Samples are made through milling, consolidation and vacuum sintering. Bars for Anti-tensile test are made through grinding and linear cutting. This paper primarily discusses the influences of milling parameters to the powder granularity and pressing property, compared and analyzes the impurity contamination situations, studies the influence of Y₂O₃ content to the microstructure and mechanic properties of the samples and gives relative explanations.When the milling speed reaches 320r/min,the powders are obviously refined and the powders is even finer when milling with balls in all sizes. Also, when milling speed reaches 320r/min, the consolidation property of the powders is improved and can be pressed without binder.When the summit sintering temperature differs from 1260oC to 1350 oC, relative densities of samples with a Y₂O₃ content increase as the increasing of the sintering temperature. With a same sintering temperature, relative densities decrease as the increasing of the Y₂O₃ content.Tensile strength of the samples rises at first and goes down latter with the increasing of the Y₂O₃ content. Maximum tensile strength get in the experiment is 669MPa when Y₂O₃ content is 1.5%.Moreover, Crystal size is refined by the addition of Y₂O₃ .