A Feasibility Study on Advanced Methodology to Produce High-Performance Nano WC-Co Granule Feedstock for Thermal Spraying

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A feasibility study was conducted, in order to fabricate WC-Co powder granule as high-performance feedstock for thermal spraying process, by spray drying weakly flocculated nano-particulate slurries under various conditions. The defects were evaluated with respect to the amount of additives to prepare spherical WC-Co feedstock powders with few morphological defects and homogeneous microstructures. The characteristics of feedstock powders heat-treated at 850~ 1200ı were analyzed using SEM, EPMA, and Hg-porosimetry. The microstructure investigation revealed that the relative portion of larger pores around 10 µm increased with increasing heattreatment temperature. On the other hand, the relative portion of smaller pores of 1 µm decreased due to the coalescence of WC particles, leading to dense feedstock powders with less defects such as hollow or craters. The hardness of thermal-sprayed coat developed with the feedstock in this study, which had exceptionally high feedstock strength, was superior to that of any other sprayed coat obtained with commercial feedstock powders.

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Periodical:

Materials Science Forum (Volumes 475-479)

Main Theme:

Edited by:

Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie

Pages:

2891-2894

Citation:

H.W. Jun et al., "A Feasibility Study on Advanced Methodology to Produce High-Performance Nano WC-Co Granule Feedstock for Thermal Spraying", Materials Science Forum, Vols. 475-479, pp. 2891-2894, 2005

Online since:

January 2005

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$38.00

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