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

Öz

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.

Anahtar Kelimeler

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

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

Öz

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.

Anahtar Kelimeler

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

Kaynakça

1. Abukhshim, N.A., Mativenga, P.T., Sheikh, M. A., 2006. Heat generation and temperature prediction in metal cutting: A review and implications for high speed machining. International Journal of Machine Tools and Manufacture, 46(7-8), 782-800.
2. Armendia, M., Garay, A., Villar, A., Davies, M.A., Arrazola, P.J., 2010. High bandwidth temperature measurement in interrupted cutting of difficult to machine materials. CIRP annals, 59(1), 97-100.
3. Da Silva, M.B., Wallbank, J., 1999. Cutting temperature: prediction and measurement methods—a review. Journal of materials processing technology, 88(1-3), 195-202.
4. Davies, M.A., Cooke, A.L., Larsen, E.R., 2005. High bandwidth thermal microscopy of machining AISI 1045 steel. CIRP Annals-Manufacturing Technology, 54(1), 63-66.
5. Ezugwu, E.O., Wang, Z.M., 1997. Titanium alloys and their machinability—a review. Journal of materials processing technology, 68(3), 262-274.
6. Hahn, R.S., 1951. On the temperature developed at the shear plane in the metalcutting process. Journal of Applied Mechanics-Transactions of the ASME, Vol. 18, No. 3, pp. 323-323.
7. Jaeger, J.C., 1942. Moving sources of heat and the temperature of sliding contacts. In Proc. Roy. Soc., NSW Vol. 176, p. 203.
8. Jiang, F., Liu, Z., Wan, Y., Shi, Z., 2013. Analytical modeling and experimental investigation of tool and workpiece temperatures for interrupted cutting 1045 steel by inverse heat conduction method. Journal of Materials Processing Technology, 213(6), 887-894.

9. Johnson, G.R., Cook, W.H., 1985. Fracture characteristics of three metals subjected to various strains, strain rates, temperatures and pressures. Engineering fracture mechanics, 21(1), 31-48.
10. Leshock, C. E., Shin, Y.C., 1997. Investigation on cutting temperature in turning by a tool-work thermocouple technique. Journal of manufacturing science and engineering, 119(4A), 502-508.
11. Longbottom, J.M., Lanham, J.D., 2005. Cutting temperature measurement while machining–a review. Aircraft Engineering and Aerospace Technology, 77(2), 122-130.
12. Ozel, T., Altan, T., 2000. Process simulation using finite element method—prediction of cutting forces, tool stresses and temperatures in high-speed flat end milling. International Journal of Machine Tools and Manufacture, 40(5), 713-738.
13. Shaw, M. C., Cookson, J.O., 1984. Metal cutting principles (pp. 183-201). Oxford: Clarendon press.
14. Stephenson, D.A., Ali, A. 1992. Tool temperatures in interrupted metal cutting. Journal of Engineering for Industry, 114(2), 127-136.
15. Stephenson, D.A., 1993. Tool-work thermocouple temperature measurements—theory and implementation issues. Journal of Engineering for industry, 115(4), 432-437.
16. Sullivan, D., Cotterell, M., 2001. Temperature measurement in single point turning. Journal of Materials Processing Technology, 118(1-3), 301-308.
17. Trent, E.M., Wright, P.K., 2000. Metal cutting. Butterworth-Heinemann.