FERRİTİK DÖKME DEMİRİN ÖSTEMPERLEME ÇALIŞMASININ DEĞERLENDİRİLMESİ

Year 2024, Volume: 11 Issue: 22, 165 - 171, 30.04.2024

Tanju Teker , Serdar Osman Yılmaz

https://doi.org/10.54365/adyumbd.1438508

Abstract

Bu çalışmada, ferritik sfero dökme demirlerin yapısal karakterizasyonuna östemperleme sıcaklıklarının etkisi analiz edilmiştir. Östemperleme, tam bir östenit yapı elde etmek için malzemelerin 900 ºC sıcaklıkta yeterli bir süre östenitlenmesi ve ardından bir aralık sıcaklığında su vermedir. Östemperleme 320, 420 ve 520 ºC' de 1.5 saat süreyle elde edilmiştir. Numunelerin metalurjik karakterizasyonu, optik mikroskopi, enerji dağılımlı spektrometri, X-ışını kırınımı, mikrosertlik kullanılarak belirlendi. Östemperleme sıcaklığı, ferritik sfero dökme demirlerin faz değişimleri üzerinde dikkate değer bir etkiye sahipti. Daha yüksek derecede östemperleme, ausferrit adı verilen daha kaba bir yapı üretti.

Keywords

Östemperleme, Mikroyapı, Ausferrite, Sertlik.

EVALUATION OF AUSTEMPERING STUDY OF FERRITIC CAST IRON

Abstract

In this study, the effect of austempering temperatures on the structural characterization of ferritic spheroid cast irons was analyzed. Austempering was the austenitization of the materials in the temperature of 900 ºC for an adequate period to obtain a complete austenite structure and then quenching to an interval temperature. Subcritical diffusion times were achieved at 320, 420, and 520 ºC ausferrite temperatures for period of 1.5 h. Metallurgical description of samples was defined using optical microscopy, energy dispersive spectrometry, X-ray diffraction, microhardness. The austempering temperature had a remarkable effect on the phase variations of the ferritic ductile cast irons. The higher degree of austempering produced a coarser structure called ausferrite.

Keywords

Austempering, Microstructure, Ausferrite, Hardness.

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