Partner: Piotr Kurp

Kielce University of Technology (PL)

Recent publications
1.Widłaszewski J., Nowak M., Nowak Z., Kurp P., Laser-assisted forming of thin-walled profiles, Metal Forming, ISSN: 0867-2628, Vol.XXVIII, No.3, pp.183-198, 2017
Abstract:

Forming processes assisted by localised laser heating are studied in recent years. Heating is used to make it possible or facilitate forming of materials, which exhibit such adverse properties as: brittleness, effects of high work-hardening or a high elastic springback. The hereby presented investigations concern the hybrid thermo-mechanical forming of thin-walled parts using local heating of the material by the laser beam. The research is aimed at forming of parts from materials used in the aviation industry, such as the nickel-base super-alloys Inconel 625, Inconel 718, and also martensitic superalloys AISI 410 and AISI 325. Preliminary investigations are conducted using X5CrNil8-10 (1.4301) stainless steel. Experimental study and numerical simulations cover the behaviour of thin beams 1 mm thick, subjected to mechanical load in the cantilever arrangement and heated by the CO2 laser beam moving from the free end of the sample towards its fixture. The possibility of obtaining large bending deformations relatively easily due to the application of laser beam is demonstrated experimentally. Experimentally verified finite element numerical simulations show the intense plastic flow of the material layer heated by the laser beam. It is accompanied by a shift of the cross-section neutral axis of the beam. Bending of thin-walled tubes in a specially designed device is studied in the next step. It allows introducing mechanical loading in a controlled manner, heating the material by a moving laser beam and forcing the required deformation according to the kinematic scheme of the device.

Keywords:

laser-assisted forming, finite element method, thin-walled structure

Affiliations:
Widłaszewski J.-IPPT PAN
Nowak M.-IPPT PAN
Nowak Z.-IPPT PAN
Kurp P.-Kielce University of Technology (PL)

Conference papers
1.Mucha Z., Widłaszewski J., Kurp P., Mulczyk K., Mechanically assisted laser forming of thin beams, Proceedings of SPIE, ISSN: 0277-786X, DOI: 10.1117/12.2262114, Vol.10159, pp.10159 0U-1-10, 2016
Abstract:

Laser-assisted forming techniques have been developed in recent years to aid plastic working of materials, which are difficult in processing at normal temperatures due to a high brittleness, effects of high work-hardening or a high spring-back phenomenon. This paper reports initial experimental investigations and numerical simulations of a mechanically-assisted laser forming process. The research is aimed at facilitating plastic shaping of thin-walled parts made of high temperature resistant alloys. Stainless steel plate, 1 mm thick, 20 mm wide, was mounted in the cantilever arrangement and a gravitational load was applied to its free end. A CO2 laser beam with rectangular cross-section traversed along the plate, towards the fixed edge. Laser spot covered the whole width of the plate. Experiments and simulations using the finite element method were performed for different values of mechanical load and with constant laser processing parameters. Experimentally validated numerical model allowed analysis of plastic deformation mechanism under the hybrid thermo-mechanical processing. The revealed mechanism of deformation consists in intense material plastic flow near the laser heated surface. This behavior results mainly from the tension state close to the heated surface and the decrease of material yield stress at elevated temperature. Stress state near the side edges of the processed plate favored more intense plastic deformation and the involved residual stress in this region. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Keywords:

laser forming, laser-assisted forming, FEA, thin-walled structure

Affiliations:
Mucha Z.-Kielce University of Technology (PL)
Widłaszewski J.-IPPT PAN
Kurp P.-Kielce University of Technology (PL)
Mulczyk K.-other affiliation

Conference abstracts
1.Nowak Z., Nowak M., Widłaszewski J., Kurp P., Experimental and numerical investigation on laser-assisted bending of pre-loaded metal plate, CMM-2017, 22nd International Conference on Computer Methods in Mechanics, 2017-09-13/09-16, Lublin (PL), No.MS13, pp.37-38, 2017
Abstract:

The laser forming technique has an important disadvantage, which is the limitation of plastic deformation generated by a single laser beam pass. In order to increase the plastic deformation one has to repeat the process several times or use the alternative method. To increase the plastic deformation it is possible to add external forces during the laser forming process. In this paper, we investigate the influence of external pre-loads on the laser bending of steel plate. The pre-loads investigated generate bending towards the laser beam. The thermal, elastic-plastic analysis is performed using the commercial nonlinear finite element analysis package ABAQUS. The focus of the paper is to identify how this pattern of the pre-load influence the final bend angle of the plate.

Keywords:

laser forming, force-assisted laser bending, thermo-mechanical simulations, FEA

Affiliations:
Nowak Z.-IPPT PAN
Nowak M.-IPPT PAN
Widłaszewski J.-IPPT PAN
Kurp P.-Kielce University of Technology (PL)
2.Mucha Z., Widłaszewski J., Kurp P., Mulczyk K., Laserowe kształtowanie cienkościennych płaskowników wspomagane mechanicznie, STL 2016, XI Sympozjum Techniki Laserowej, 2016-09-27/09-30, Jastarnia (PL), pp.41, 2016