Selection of Protective Coatings Obtained by Plasma Spraying Method for Foundry Industry

Abstract:

The paper presents the results of studies of protective coatings for graphite moulds, which were used in copper casting process. The following coatings were involved: Mo, NiAl, NiCrAl, Cr₃C₂-NiCr, WC-CrC-Ni. All tested coatings were applied on the graphite substrate by plasma spraying method. The microstructure was investigated by optical microscopy (OM) and scanning electron microscopy (SEM). The microhardness of coatings was measured by Vickers method. The wettability of coatings by liquid copper was evaluated. It was found that NiAl and NiCrAl coatings had the highest limiting wetting angle and consequently the lowest wettability among all the examined coatings. It was also found that chemical composition strongly influenced the coating properties.

• Periodical: Key Engineering Materials (Volume 682)
• Pages: 177-181
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.682.177
• Online since: February 2016
• Authors: Maria Richert*, Beata Leszczyńska-Madej, Ilona Nejman, Paulina Zawadzka, Stanislaw Pietrzyk
• Keywords: Foundry Industry, Microstructure, Plasma Spraying, Wettability

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