Auto-detection of Intermetallic and Eutectic Phases in Microstructure of the AZ91 Mg-alloys by Image Processing Techniques

Öz

AZ91, which is used in the production of parts in the aerospace, defense and automotive industries, can be enhanced by the addition of an alloying element or the cooling rate, due to the weak strength and formability properties of advanced technology Mg-alloys. The microstructure change in Mg alloys significantly affects the mechanical properties. By analyzing the microstructure of these alloys, a close estimate of the mechanical properties can be made. In this study, an image processing-based model is proposed that automatically recognizes the intermetallic and eutectic phases required for the analysis of microstructural properties in AZ91 Mg-alloys. The proposed method consists of two stages; In the first step, the eutectic phase template is obtained as a binary image. In the second step, the binary image containing the intermetallic and eutectic phases is obtained and the result image with only the intermetallic phases is obtained by taking the difference of these two patterns. Experimental studies have shown that the proposed method gives a result close to the real value in the detection of eutectic phases.

Anahtar Kelimeler

• AZ91 Mg-alloys
• Image Processing
• Microstructure
• Intermetallic Phase
• Eutectic Phase

AZ91 Mg Alaşımlarının Mikroyapısındaki İntermetalik ve Ötektik Fazların Görüntü İşleme Teknikleriyle Otomatik Tespiti

Öz

Havacılık, savunma ve otomotiv endüstrilerinde parça üretiminde kullanılan AZ91, ileri teknoloji Mg alaşımlarının zayıf mukavemet ve şekillendirilebilirlik özelliklerinden dolayı bir alaşım elementi ilavesi veya soğutma hızı ile geliştirilebilir. Mg alaşımlarındaki mikroyapı değişimi, mekanik özellikleri önemli ölçüde etkiler. Bu alaşımların mikroyapısı incelenerek, mekanik özellikler hakkında yakın bir tahminde bulunulabilir. Bu çalışmada, AZ91 Mg alaşımlarında mikroyapı özelliklerinin analizi için gerekli olan intermetalik ve ötektik fazları otomatik olarak tanımayı sağlayan görüntü işleme tabanlı bir model önerilmiştir. Önerilen yöntem iki aşamadan meydana gelmektedir; ilk aşamada ikili görüntü olarak ötektik faz şablonu elde edilir. İkinci aşamada ise intermetalik ve ötektik fazları içeren ikili görüntü elde edilir ve bu iki şablonun farkı alınarak yalnızca intermetalik fazların olduğu sonuç görüntüsüne ulaşılır. Yapılan deneysel çalışmalarda, önerilen yöntemin ötektik fazların tespitinde gerçek değere yakın bir sonuç verdiğini göstermiştir.

Anahtar Kelimeler

• AZ91 Mg Alaşımları
• Görüntü İşleme
• Mikroyapı
• İntermetalik Faz
• Ötektik Faz

Kaynakça

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