Strength Optimization of Resistance Spot Welded TWIP Steel by Taguchi Method

Abstract

The microstructure and mechanical properties of TWIP (TWinning Induced Plasticity) sheets, one of the members of Advanced High Strength Steel (AHSS), are affected by excessive thermal cycles such as welding and heat treatment. In this study, TWIP steel sheets are joined with the resistance spot weld in various welding parameters for optimization of the strength and weld nugget geometry. For this purpose, the optimization of the tensile shear strength and weld nugget diameter of the weldments were determined by using Taguchi experimental design method and L9 orthogonal array was chosen. Based on the analysis test results, the optimum welding parameter which provides the best strength and weld nugget quality for the resistance spot welded TWIP steel was determined by Taguchi analysis as 7kA welding current and 20 cycle welding time (A2B3). It has been determined that the most effective variable for weld nugget diameter value is welding time, while the most important welding parameter for effecting tensile shear strength is the welding current. 

Keywords

• TWIP steels; Taguchi method; Tensile shear strength; Weld nugget diameter

Taguchi Yöntemi ile Nokta Direnç Kaynaklı TWIP Çeliklerin Dayanım Optimizasyonu

Abstract

İleri yüksek mukavemetli çeliklerin (Advanced High Strength Steel-AHSS) üyelerinden biri olan TWIP (TWinning Induced Plasticity- İkizlenmeyle plastisite kazanan) çeliklerin mikroyapı ve mekanik özellikleri, kaynak ve ısıl işlem gibi yüksek termal döngülerden etkilenirler. Bu çalışmada, mukavemet ve kaynak çekirdek geometrisinin optimizasyonu için çeşitli kaynak parametrelerinde TWIP çelik saclar nokta direnç kaynağı ile birleştirilmiştir. Bu amaçla, deney numunelerinin çekme makaslama dayanımı ve kaynak çekirdek çapının optimizasyonu Taguchi deneysel tasarım yöntemi kullanılarak belirlenmiş ve L9 ortogonal dizini seçilmiştir. Analiz test sonuçlarına dayanarak, Taguchi analiziyle belirlenen nokta direnç kaynaklı TWIP çeliği için en iyi mukavemet ve kaynak çekirdek kalitesini veren optimum kaynak parametresi, 7 kA kaynak akımı ve 20 çevrim kaynak zamanı (A2B3) olarak belirlenmiştir. Çekme makaslama dayanımının etki eden en önemli kaynak parametresi kaynak akımı iken, kaynak çekirdek çapı değeri için en etkili değişkenin kaynak zamanı olduğu belirlenmiştir.

Keywords

• TWIP çelikleri,Taguchi metodu,Çekme makaslama dayanımı,Kaynak çekirdek çapı

References

1. [1] H. B. Cary, Modern Welding Technology, 3rd ed., Prentice Hall, Upper Saddle River, NJ 1994.
2. [2] Z. Han, J. E. Indacochea, C. H. Chen, and S. Bhat, “Weld nugget development and integrity in resistance spot welding of high-strength cold-rolled sheet steels”, Welding Journal, vol. 72 no. 5, pp. 209, 1993.
3. [3] H. L. Lin, T. Chou, and C. P. Chou, “Optimization of resistance spot welding process using taguchi method and a neural network”, Experimental Techniques, pp. 30-36, 2007.
4. [4] H. Eisazadeh and M. Hamedi, “New parametric study of nugget size in resistance spot welding process using finite element method”, Material and Design, vol.31, pp. 149-157, 2010.
5. [5] A. G. Thanur and V. M. Nandedkar, “Application of Taguchi method to determine resistance spot welding conductions of austenitic stainless AISI 304”, Journal of scientific & Industrial research, vol. 69, pp. 680-68, 2010.
6. [6] M. Pouranvari, H.R. Asgari, S.M. Mosavizadch, P. H. Marashi and M. Goodarzi, “Effect of weld nugget size on overload failure mode of resistance spot welds”, Science and Technology of Welding and Joining, vol. 12, no. 3, pp. 217-225, 2007.
7. [7] J. Heuschkel, “The expression of spot-weld properties”, Welding Journal, vol. 31, no.10, pp. 931-943,1952.
8. [8] M. Zhou, H. Zhang and S. J. Hu, “Relationships between Quality and Attributes of Spot Welds” Weld. J., vol. 82, pp. 72–77, 2003.

9. [9] American Welding Society: “Recommended practices for test methods for evaluating the resistance spot welding behavior of automotive sheet steel materials”, ANSI/AWS/SAE/D8 .9-97, 1997.
10. [10] J. S. Kwak, “Application of taguchi and response surface methodologies for geometric in surface grinding process”, International Journal of Machine Tools & Manufacture, vol. 45, pp. 327-334, 2005.
11. [11] N. Muhammad, Y.H.P. Manurung, M. Hafidzi, S. K. Abas, G. Tham and E. Haruman, “Optimization and modeling of spot welding parameters with simultaneous multiple response consideration using multi-objective Taguchi method and RSM”, Journal of Mechanical Science and Technology, vol. 26, no.8, pp. 2365–2370, 2012.
12. [12] M. Karabatak and M. Kara, F. “Experimental optimization of surface roughness in hard turning of AISI D2 cold work tool steel”, Journal of Polytechnic, vol. 19, pp. 349-355, 2016.
13. [13] M. Boy, İ. Çiftci, M. Günay and F. Ozhan, “Application of the Taguchi method optimize the cutting conditions in hard turning of a ring bore”, Materials and technology, vol. 49, no.5, pp. 765–772, 2015.
14. [14] M. Günay and E. Yücel, “Application of Taguchi method for determining optimum surface roughness in turning of high-alloy white cast iron”, Measurement, vol. 46, pp. 913–919, 2013.
15. [15] H. Sing and P. Kumar, “Optimization cutting force for turned part using Taguchi’s parameter design approach”, Indian Journal Eng Mater Sci, 12, pp. 97-103, 2015.
16. [16] A.G. Thakur and V. M. Nandedkar, “Application of Taguchi method to determine resistance spot welding conductions of austenitic stainless AISI 304”, Journal of scientific & Industrial research, vol. 69, pp. 680-68, 2010.
17. [17] D. Chandra Saha, S. Han, K.G. Chin, I. Choi and Y. D. Park, “Weldability evaluation and microstructure analysis of resistance-spot-welded High-Mn steel in automotive application”, Steel Research Int., vol 83, pp. 1-6, 2012.
18. [18] F. Kara, “Taguchi optimization of surface roughness and flank wear during the turning of DIN1.2344 tool steel”, Materials Testing, vol.59, pp. 903-908, 2017.
19. [19] F. Kara and B.Öztürk, “Comparison and optimization of PVD and CVD method on surface roughness and flank wear in hard-machining of DIN 1.2738 mold steel”, Sensor Review, 2018.
20. [20] H.L Lin and C.P. Chou “Optimisation of The GTA Welding Process Using The Taguchi Method and a Neural Network’’, Science and Technology of Welding & Joining, vol. 11, pp. 120 –128, 2006.
21. [21] S. Pandiarajan, S. Senthil Kumaran , L.A. Kumaraswamidhas and R. Saravanan “Interfacial microstructure and optimization of friction welding by Taguchi and ANOVA method on SA 213 tube to SA 387 tube plate without backing block using an external tool”, Journal of Alloys and Compounds, vol. 654, pp. 534- 545, 2016.
22. [22] U. Eşme, “Application of Taguchi Method for the Optimization of Resistance Spot Welding Process”, The Arabian Journal for Science and Engineering, vol.34, pp.519-528,Oct.2009
23. [23] G. Mukhopadhyaya, S. Bhattacharya, and K.K. Ray, “Strength assessment of spot-welded sheets of interstitial free steels”, Journal of Materials Processing Technology, vol. 209, pp.1995-2007, 2009.
24. [24] A.G. Thakur, T. E. Rao, M. S. Mukhedkar and V. M. Nandedkar, “Application of Taguchi method for resistance spot welding of galvanized steel”, ARPN Journal of Engineering and Applied Sciences, vol. 5, pp. 22-26, 2010.
25. [25] A. A. Karad, V. S. Shete and N. V. Boraste, “Optimization of resistance spot welding process parameter by taguchi method”, International Journal of Engineering Research and General Science, vol. 4, no. 2, pp. 679-684, 2016.
26. [26] N. K. Singh and Y. Vijayakumar, “Application of Taguchi method for optimization of resistance spot welding of austenitic stainless steel AISI 301L”, Innovative Systems Design and Engineering vol. 3, pp.50-62, 2012.
27. [27] S. Athreya and Y. D. Venkatesh, “Application of taguchi method for optimization of process parameters in improv-ing”, The Surface Roughness of Lathe Facing Operation International Refereed Journal of Engineering and Science (IRJES), vol. 1, no. 3, pp. 13-19, 2012.
28. [28] M. Tutar, H. Aydin, A. Bayram, “Multi objective Taguchi optimization approach for resistance spot welding of cold rolled TWIP steel sheets”, IOP Conf. Series: Journal of Physics: Conf. Series, vol. 885, 2017.
29. [29] M. Pouranvari, S. P. H. Marashi and D. S. Safanama, “Failure mode transition in AHSS resistance spot welds – Part II: Experimental investigation and model validation”, Materials Science and Engineering: A vol. 528, no. 29, pp. 8344 – 8352, 2011).
30. [30] M. Kurt, Y. Kaynak, B. Bakır, U. Köklü, G. Atakök ve L. Kutlu, “Al 2024- T4 Alüminyumun elmas benzeri karbon (DLC) kaplanmış matkaplarla delinmesinde kesme parametrelerinin deneysel incelenmesi ve taguchi optimizasyonu”, 5. Uluslararası İleri Teknolojiler Sempozyumu (IATS’09), 13- 15 Mayıs 2009.