Alloying Element Nb Effect on Microstructure of Co-Al-W Superalloy by Vacuum Arc Melting


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Co-Al-W supperalloy used pure element powder, according to the ratio of different atomic percentage composition to make ingredients. It is mixed by planetary ball mill, pressed into blocks after the melting shape. Vacuum arc melting process was prepared by melting, after grinding, polishing, and after a volume of 5% perchloric acid and 95% of the electrolytic etcheing solution prepared in ethanol corrosion observed after analysis of the microstructure and phase composition by XRD analysis .It can be found that Co-Al-W superalloys were mainly composed of cobalt-rich matrix of austenite precipitation of γ phase and coherent with matrix of the L12 structure of γ′-Co3(Al,W) phase. In addition, Nb have effect on grain refinement and refine grain. Rockwell hardness test and analysis, It can be found that Nb can clearly improve the Co-Al-W superalloy hardness.



Edited by:

Mohamed Othman




Y. T. Xu et al., "Alloying Element Nb Effect on Microstructure of Co-Al-W Superalloy by Vacuum Arc Melting", Applied Mechanics and Materials, Vols. 229-231, pp. 63-67, 2012

Online since:

November 2012




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