Soner BUYTOZ, M. Mustafa YILDIRIM, Hülya EREN

TIG metodu kullanılarak yapılan Fe-Cr-C kaplamalarının karakterizasyonu

Fe-Cr-C kaplamalarının mikroyapısı deneysel olarak incelendi. Kaplamalar, AISI 4340 çelik yüzeyinde bir gaz tungsten ark torcu vasıtasıyla oluşturuldu. Kaplama mikroyapılarında ostenit matrisi içinde katılaşmış ve dağılmış $(Cr,Fe)_7C_3$ karbürleri tespit edildi. $(Cr,Fe)_7C_3$ karbürleri ile $(Cr,Fe)_7C_3+(gamma)$ içeren mikroyapılar ötektik üstü mikroyapılardır. $(Cr,Fe)_7C_3$ karbürlerinin sertlik değerleri 1500 HV iken $(Cr,Fe)_7C_3+(gamma)$ matrisin sertlik değerleri 750 HV olarak tespit edildi.

Characterization of Fe-Cr-C coatings used TIG method

The microstructure of Fe-Cr-C coatings was experimentally investigated. The coatings were formed by means of a gas tungsten arc torch on the AISI 4340 steel. The microstructures of the coatings are found to composed of primary $M_7C_3$ carbides in eutectic of austenite matrix. The hypereutectic microstructure consisted of $M_7C_3$ and $M_7C_3+austenite(gamma)$. The hardness values of $M_7C_3$ carbides varied between 1050-1500 HV, while the hardness of $M_7C_3+austenite(gamma)$ matrix was measured between 500-750 HV.

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