Na2SO4-V2O5-NaCI Tuzuna Maruz Bırakılan Inconel 718 Süper Alaşım Malzemesinin Yüksek Sıcaklıkta Sıcak Korozyon Davranışı

Öz

Inconel 718 süper alaşımı, havacılık ve uzay endüstrisinde sıcak korozyona karşı dayanıklılığıyla bilinse de düşük kaliteli yakıtların neden olduğu agresif ortamlarda ciddi yapısal hasarlara maruz kalabilmektedir. Bu çalışmada, %35 Na2SO4 + %35 V2O5 + %30 NaCl tuz karışımı, Inconel 718 altlık üzerine uygulanarak 900 °C ± 25°C sıcaklıkta 1, 3, 5 ve 24 saatlik sıcak korozyon testleri gerçekleştirilmiştir. Test öncesi ve sonrası mikroyapısal değişimler SEM, EDS, elementel haritalama ve XRD ile analiz edilmiştir. Bulgular, kısa süreli maruziyetlerde sınırlı oksitlenme görülürken, 24 saatlik sürede yüzeyde belirgin faz dönüşümleri ve yapısal bozulmaların başladığını göstermiştir. Bu sonuç, Inconel 718’in yüksek sıcaklıkta agresif tuz ortamlarına karşı dayanımının zamanla azaldığını ortaya koymaktadır.

Anahtar Kelimeler

• süper alaşımlar
• tel erozyon yöntemi
• havacılık ve uzay endüstrisi
• termal bariyer kaplamalar

High-Temperature Hot Corrosion Behavior of Inconel 718 Superalloy Material Exposed to Na2SO4-V2O5-NaCI Salt

Abstract

Although Inconel 718 superalloy is known for its resistance to hot corrosion in the aerospace industry, it can be subjected to severe structural damage in aggressive environments caused by low-quality fuels. In this study, a 35% Na2SO4 + 35% V2O5 + 30% NaCl salt mixture was applied on an Inconel 718 substrate, and hot corrosion tests were performed at 900°C ± 25°C for 1, 3, 5, and 24 hours. Microstructural changes before and after the tests were analyzed by SEM, EDS, elemental mapping, and XRD. The results showed that while limited oxidation was observed in short-term exposures, significant phase transformations and structural deterioration started on the surface at 24 hours. This result reveals that the resistance of Inconel 718 to aggressive salt environments at high temperatures decreases over time.

Keywords

• Superalloys
• wire erosion method
• aerospace industry
• thermal barrier coatings

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