CUTTING TEMPERATURE MEASUREMENT BY THERMAL CAMERA AND FINITE ELEMENT MODELING DURING MACHINING OF Tİ6Al4V ALLOY

Abstract

Machining, or metal cutting, is one of the most common manufacturing processes. Cutting temperature can be stated as one of the most important problems in machining due to its effects on the machined part surface integrity, part tolerances and the tool wear so on the manufacturing cost. In this study, the cutting temperatures are determined during machining of Ti6Al4V titanium alloy. Cutting temperatures were measured by a thermal imaging system in which the most important problem is choosing the right emissivity value of the measured surface. Hence, an experimental setup was designed and the emissivity value of Ti alloy was determined. Then, the cutting temperatures were predicted by developed finite element model. The experimental and theoretical results were compared and a very good match was achieved.

Keywords

• Machining,Cutting temperature,Thermal camera,Finite element model

Ti6Al4V ALAŞIMININ TALAŞLI İMALATI SIRASINDA TERMAL KAMERA İLE SICAKLIK ÖLÇÜMÜ VE SONLU ELEMANLARLA MODELLENMESİ

Abstract

Talaşlı imalat en yaygın kullanılan imalat yöntemlerinden biridir. Talaşlı imalatta en önemli problemlerin başında yüzey bütünlüğünü, parça toleransını ve takım ömrünü dolayısıyla maliyeti etkilemesi nedeniyle kesme sıcaklığı gelmektedir. Özellikle titanyum, nikel gibi kesilmesi zor alaşımların işlenmesinde kesme sıcaklığının etkileri daha belirgin olmaktadır. Bu amaçla, bu çalışmada Ti6Al4V alaşımının kesilmesi sırasında sıcaklıkların belirlenmesine çalışılmıştır. Kesme sıcaklıkları deneysel olarak termal kamera ile ölçülmüştür. Termal kamera ile yapılan ölçümlerde karşılaşılan en büyük problem uygun yayma katsayısı (emissivite) değerinin seçilmesidir. Bu nedenle çalışmada yayma katsayısının belirlenmesi için bir deney düzeneği tasarlanmıştır. Sonrasında ise bu sıcaklıklar sonlu elemanlar yardımı ile modellenmiştir. Deneysel ve teorik sonuçlar karşılaştırılmış ve birbirine oldukça yakın sonuçlar elde edilmiştir.

Keywords

• Talaşlı imalat,Kesme sıcaklığı,Termal kamera,Sonlu elemanlar

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