Characterization of Microstructure and Bending Response of Sheet Material: Influence of Thickness
الموضوعات :Mustafa Özdemir 1 , Hakan Gökmese 2 , H Dilipak 3 , V Yilmaz 4
1 - Machine and Metal Technology Department, Vocational High School, Bozok University, Yozgat, Turkey
2 - Materials and Metallurgical Department, Engineering Faculty, Necmettin Erbakan University, Konya, Turkey
3 - Manufacturing Engineering Department, Tecnology Faculty, Gazi University, Ankara, Turkey
4 - Motor Vehicles and Transportation Technologies Department, Kazan Vocational High School, Gazi
University, Ankara, Turkey
الکلمات المفتاحية: Spring-go, V-die bending, Metal forming,
ملخص المقالة :
Bending process is one of the most significant fields of application of sheet metal die. In bending process, it is quite vital that the product should have the desired angle. Furthermore, in order to obtain the desired angle in the bent parts, spring-go and spring-back amounts must be known. In this study, 30o, 60o and 90o bending processes were applied to S235JR (1.0038) sheet metal having 3, 4, 5 and 6 mm thickness. These materials were bent in three forms as heat-untreated, normalized and tempered. In addition to this, the bending process was carried out by making the punch waited on the material for 30 seconds (30 s-punch-wait bending) and by removing the punch without waiting (direct bending). As a result of the experiments it was determined that while the amount of spring-go increased in 30o bending process depending on the thickness of the material, it decreased in 60o and 90o applications. It was also determined that the amount of spring-go in 30 s punch-wait bending process was less than that of the direct bending process. Finally, the effects on the bending process and deformation of heat treatment were revealed by micro-structural characterization.
[1]. Ozdemir, M.; Gökmeşe, H.; Dilipak, H.; Yılmaz, V. ‘’Investigation as Experimental and Micro-structural of the Effect to Spring back/forward Amount of 16Mo3 (1.5415) Sheet Materials of Different Heat-Treatments’’, ISITES, Turkey, 2014, pp. 148-155.
[2]. Bakhshi J.; Rahmani B.; Daeezade V.; Gorji, A. The Study of Spring-Back of CK67 Steel Sheet in V-Die and U- Die Bending Processes. Materials and Design 2009, 30, 2410-2419.
[3]. Ragai L.; Lazim D.; Nemes A. Anisotropy and Spring-back in Draw-Bending of Stainless Steel 410 Experimental and Numerical Study. Journal of Materials Processing Technology 2005, 166, 116-127.
[4]. Branko G.; Josip C.; Dejan G. Effect of Spring-Back and Spring-Forward in V-Die Bending of St1403 Sheet Metal Plates, Journal for Theory and Appl. in Mech Engineering 2010, 52, 181-186.
[5]. Thipprakmas S. Finite Element Analysis on the Coined-bead Mechanism during the V-Bending Process. Materials and Design 2011, 32,4909-4917.
[6]. Imai K.; Koyama J.; Jin Y. High-Accuracy V-Bending System by Real Time Identifying Material Property. Journal of Materials Processing Technology 2008, 201, 193-197.
[7]. Li, X.; Yang, Y.; Wang, Y.; Bao, J.; Li, S. Effect of the material-hardening mode on the spring-back simulation accuracy of V-free bending. Journal of Materials Processing Technology 2002, 123, 209–211.
[8]. Thipprakmas S.; Rojananan S. Investigation of Spring-go Phenomenon Using Finite Element Method.Materials and Design 2008, 29, 1526-1532.
[9]. Thipprakmas S.; Phanitwong, W. Process parameter design of spring-back and spring-go in V-bending process using Taguchi technique, Materials and Design 2011, 32, 4430–4436.
[10]. Thipprakmas S. Finite element analysis of punch height effect on V-bending angle. J Mater Des 2010, 31, 1593–8.
[11]. Thipprakmas S. Effect of ratio of punch height to workpiece length in partial Vbending process. Steel Res Int 2010, 81, 769–72.
[12]. Panthi SK, Ramakrishnan N, Ahmed M, Singh SS, Goel MD. Finite element analysis of sheet metal bending process to predict the springback. J Mater Des 2010, 31, 657–62.
[13]. Dilipak, H.; Ozdemir, M.; Sarıkaya, M. Effects of Material Properties and Punch Tip Radius on Spring-go in 90° V Bending Processes. Journal of Iron and Steel Research, Internatıonal 2013, 20, 64-69.
[14]. Ozdemir, M.; Dilipak, H. S235JR (1.0038) Sac Malzemeye Uygulanan Isıl İşlemlerin İleri Esneme Miktarına Etkisinin Deneysel Olarak İncelenmesi, 3. Ulusal Talaşlı İmalat Sempozyumu, Turkey, 2012, 345-353.
[15]. Parsa, M.-H.; Nasher al ahkami, S.; Pishbin, H.; Kazemi, M. Investigating spring back phenomena in double curved sheet metals forming, Materials and Design 2012,41, 326-337.
[16]. Kumar, D. K.; Appukuttan, K.K.; Neelakantha, V.L.; Padmayya, S.N. Experimental determination of spring back and thinning effect of aluminum sheet metal during L-bending operation. Materials and Design 2014, 56, 613-619.
[17]. Tekaslan O.; Şeker U.; Gerger N. Determination of Copper Sheet Metal in “V” Bending Dies. Journal of the Faculty of Engineering and Architecture of Gazi University 2008, 23, 231-238.
[18]. Tekaslan O.; Gerger, N.; Şeker U. Determination of spring-back of stainless steel sheet metal in “V” bending dies, Materials and Design 2008, 29, 1043-1050.
[19]. Ozdemir M. The Experimental Investigation of Spring-Back of S235JR Sheet Metals within Bending Die. Master Thesis, Gazi University, Ankara, 2011.
[20]. Savaşkan, T., Malzeme Bilgisi ve Muayenesi, Karadeniz Teknik Üniversitesi Makine Mühendisliği Bölümü, Trabzon, 2004, pp. 30-80.
[21]. Dieter, G.-E. Workability Testing Tecniques, ASM International, Ohio, 2003, pp. 16-48.
[22]. Fang, F.; Hu, X.;Zhang, B.; Xie, Z.; Jiang, J. Deformation of dual-structure medium carbon steel in cold drawing,Materials Science&Engineering 2013, 583, 78–83.
[23]. Yan, P.; Liu, Z.; Bao, H.; Weng, Y.; Liu, W. Effect of normalizing temperature on the strength of 9Cr–3W-3Co martensitic heat resistant steel. Materials Science&Engineering 2014, 597, 148–156.
