|تعداد مشاهده مقاله||111,529,767|
|تعداد دریافت فایل اصل مقاله||86,163,139|
Study on the Effect of Laser Welding Parameters on the Microstructure and Mechanical Properties of Ultrafine Grained 304L Stainless Steel
|Journal of Ultrafine Grained and Nanostructured Materials|
|مقاله 10، دوره 49، شماره 2، اسفند 2016، صفحه 120-127 اصل مقاله (1.41 M)|
|نوع مقاله: Research Paper|
|شناسه دیجیتال (DOI): 10.7508/jufgnsm.2016.02.10|
|Reihane Nafar Dehsorkhi* ؛ Soheil Sabooni؛ Abdoulmajid Eslami؛ Fathallah Karimzadeh؛ Behzad Sadeghian|
|Department of Materials Engineering, Isfahan University of Technology, Isfahan, 84156-83111, Iran.|
|In the present study, an ultrafine grained (UFG) 304L stainless steel with the average grain size of 300 nm was produced by a combination of cold rolling and annealing. Weldability of the UFG sample was studied by Nd: YAG laser welding under different welding conditions. Taguchi experimental design was used to optimize the effect of frequency, welding time, laser current and laser pulse duration on the resultant microstructure and mechanical properties. X-ray Diffraction (XRD), Optical Microscope (OM), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), microhardness measurements and tension tests were conducted to characterize the sample after thermomechanical processing and laser welding. The results showed that the ultrafine grained steel had the yield strength of 1000 Mpa and the total elongation of 48%, which were almost three times higher than those of the as-received sample. The microstructure of the weld zone was shown to be a mixture of austenite and delta ferrite. The microhardness of the optimized welded sample (315 HV0.5) was found to be close to the UFG base metal (350 HV). It was also observed that the hardness of the heat affected zone (HAZ) was lower than that of the weld zone, which was related to the HAZ grain growth during laser welding. The results of optimization also showed that the welding time was the most important parameter affecting the weld strength. Overall, the study showed that laser welding could be an appropriate and alternative welding technique for the joining of UFG steels.|
|304 stainless steel؛ Ultrafine grain؛ Laser welding؛ Taguchi experimental design|
1. Davis J. ASM Specialty Handbook–Stainless Steels. Materials Park, USA, ASM International. 1994.
2. Lo KH, Shek CH, Lai JK. Recent developments in stainless steels. Materials Science and Engineering: R: Reports. 2009;65(4):39-104.
3. Karjalainen LP, Taulavuori T, Sellman M, Kyrolainen A. Some strengthening methods for austenitic stainless steels. Steel Research International. 2008;79(6):404.
4. Song R, Ponge D, Raabe D, Speer JG, Matlock DK. Overview of processing, microstructure and mechanical properties of ultrafine grained bcc steels. Materials Science and Engineering: A. 2006;441(1):1-7.
5. Sabooni S, Karimzadeh F, Enayati MH, Ngan AH. The role of martensitic transformation on bimodal grain structure in ultrafine grained AISI 304L stainless steel. Materials Science and Engineering: A. 2015;636:221-30.
6. Rezaee A, Kermanpur A, Najafizadeh A, Moallemi M, Baghbadorani HS. Investigation of cold rolling variables on the formation of strain-induced martensite in 201L stainless steel. Materials & Design. 2013;46:49-53.
7. Momeni A, Abbasi SM. Repetitive thermomechanical processing towards ultrafine grain structure in 301, 304 and 304L stainless steels. Journal of Materials Science & Technology. 2011;27(4):338-43.
8. Weng Y, editor. Ultra-fine grained steels. Springer Science & Business Media; 2009.
9. Mazumder J. Laser welding: state of the art review. Journal of the Minerals, Metals & Materials Society. 1982;34(7):16-24.
10. Mackwood AP, Crafer RC. Thermal modelling of laser welding and related processes: a literature review. Optics & Laser Technology. 2005;37(2):99-115.
11. Lippold JC. Solidification behavior and cracking susceptibility of pulsed-laser welds in austenitic stainless steels. Welding Journal Including Welding Research Supplement. 1994;73(6):129-139.
12. Guo W, Kar A. Prediction of microstructures in laser welding of stainless steel AISI 304. Journal of Laser Applications. 1999;11(4):185-9.
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