Production of WC-Co-TiC Cermets by Electric Current Assisted Sintering Method and Investigation of Electrochemical Properties

Abstract

Within the scope of this study, using the Electric Current Assisted Sintering (ECAS) method, the production of WC-Co and WC-Co materials with TiC additives in the ratios of 5%, 7.5% and 10% by weight were carried out in about 6 minutes in the 600-4500A current range and the effect of TiC on properties was investigated depending on the amount. From the SEM examinations, it was observed that the undoped WC-Co sample had a uniform structure, the added TiC particles had a harmonious union with the matrix and were uniformly distributed within the structure. WC, Co peaks and TiC were added to samples without additives based on XRD patterns, and WC, Co peaks as well as TiC peaks were also detected. The relative densities of the undoped WC-Co and the samples with 5%, 7.5%, 10% TiC by weight were calculated as 98.77%, 96.42%, 95.91% and 95.33%, respectively, microhardness values were determined as 1299 HV0.5, 1402 HV0.5, 1581 HV0.5 and 1768 HV0.5. Electrochemical corrosion studies were carried out in 3.5% NaCl solution by weight and the corrosion rates of the samples were determined as 96.25 mpy, 89.13 mpy, 87.64 mpy and 72.41 mpy, respectively. As a result of the studies carried out, it was determined that the relative densities decreased with the increase in the amount of TiC, while the hardness values increased and the corrosion properties improved.

Keywords

• WC-Co-TiC
• Cermets
• Electric current activated sintering
• Electrochemical corrosion

WC-Co-TiC Sermetlerinin Elektrik Akımı Destekli Sinterleme Yöntemi ile Üretimi ve Elektrokimyasal Özelliklerinin İncelenmesi

Abstract

Bu çalışma kapsamında, Elektrik Akımı Destekli Sinterleme (ECAS) yöntemi kullanılarak 600-4500A akım aralığında yaklaşık 6 dakika gibi bir sürede WC-Co ve ağırlıkça %5, %7,5 ve %10 oranlarında TiC katkılı WC-Co malzemelerinin üretimleri gerçekleştirilmiş ve katkı miktarına bağlı olarak TiC’ ün özellikler üzerine etkisi incelenmiştir. SEM incelemelerinden katkısız WC-Co numunesinin uniform bir yapıya sahip olduğu, ilave edilen TiC partiküllerinin matris ile uyumlu bir birleşme gösterip, yapı içerisinde üniform dağıldığı görülmüştür. XRD paternlerinden katkısız numunede WC, Co pikleri ve TiC ilave edilen numunelerde ise WC, Co piklerinin yanı sıra TiC piki de tespit edilmiştir. Katkısız WC-Co ve ağ. %5, %7.5, % 10 TiC katkılı numunelerin nispi yoğunlukları sırasıyla %98.77, %96.42, %95.91 ve %95.33 olarak hesaplanırken, mikrosertlik değerleri 1299 HV0.5, 1402 HV0.5, 1581 HV0.5 ve 1768 HV0.5 olarak belirlenmiştir. Elektrokimyasal korozyon çalışmaları Ağ.%3.5 NaCl çözeltisi içerisinde gerçekleştirilmiş olup numunelerinin korozyon hızları sırasıyla 96.25 mpy, 89.13 mpy, 87.64 mpy ve 72.41 mpy olarak tespit edilmiştir. Yapılan çalışmalar sonucunda TiC miktarının artmasıyla nispi yoğunluklarda azalma gözlenirken sertlik değerlerinin arttığı ve korozyon özelliklerinin iyileştiği belirlenmiştir.

Keywords

• WC-Co-TiC
• Sermetler
• Elektrik akımı destekli sinterleme
• Elektrokimyasal korozyon

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