Microstructure Characterization of WCCo-Mo Based Coatings Produced Using High Velocity Oxygen Fuel

Abstract

The present study has been carried out in order to investigate the microstructural properties of WCCo-Mo composite coatings deposited onto a SAE 4140 steel substrate by high velocity oxygen fuel (HVOF) thermal spray. For this purpose, the Mo quantity added to the WCCo was changed as 10, 20, 30 and 40 wt. % percents. The coatings are compared in terms of their phase composition, microstructure and hardness. Phase compound and microstructure of coating layers were examined using X-ray diffractometer (XRD) and scanning electron microscope (SEM). XRD results showed that WCCo-Mo composite coatings were mainly composed of WC, W2C, Co3W3C, Mo2C, MoO2, Mo and Co phases. The average hardness of the coatings increased with increasing Mo content.

Keywords

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Yüksek Hızlı Oksi Yakıt ile Üretilen WCCo-Mo Esaslı Kaplamaların Mikroyapı Karakterizasyonu

Öz

Bu çalışma, yüksek hızlı oksi yakıt (HVOF) ısıl püskürtme yöntemi ile SAE 4140 çeliği üzerinde üretilen WCCo-Mo kompozit kaplamaların mikroyapısal özelliklerini araştırmak için yapılmıştır. Bu amaç için WCCo tozlarına ilave edilen Mo miktarı % ağ. 10, 20, 30 ve 40 olarak değiştirilmiştir. Kaplamalar, faz bileşimi, mikroyapı ve sertlik özellikleri açısından karşılaştırılmıştır. Kaplama tabakalarının faz bileşimi ve mikroyapısı X-ışını difraktogramı (XRD) ve taramalı elektron mikroskobu (SEM) ile incelenmiştir. XRD sonuçları, WCCo-Mo kaplama tabakasının WC, W2C, Co3W3C, Mo2C, MoO2, Mo ve Co fazlardan oluştuğunu göstermiştir. Kaplamaların sertliği Mo artışı ile artmıştır.

Anahtar Kelimeler

• Mo, WCCo, HVOF, Mikroyapı, Sertlik

Kaynakça

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