0000000000084100
AUTHOR
Gabriel Racz
Study of the Formability of Laminated Lightweight Metallic Materials
The main objective of this work was to test the formability of laminated materials. Laminated materials are considered a good choice when parts with reduced weight are considered. Thus, a laminated material, aluminum - polypropylene - aluminum (Al-PP-Al), as sheet 1.2 mm and 1.4 mm thickness was used. Before processing the material by means of unconventional plastic deformation, its formability was determined by running the Nakajima test. After obtaining the forming limit curves, the material was machined by means of incremental forming.
Simulated 3-axis versus 5-axis Processing Toolpaths for Single Point Incremental Forming
Abstract Accuracy and productivity of the parts manufactured by single point incremental forming (SPIF) are influenced by the proper selection of toolpaths. CAM software packages are often used for generating the toolpaths for the process. Literature survey have revealed that contour curves and spatial spirals are the most used toolpaths for SPIF. These toolpaths are generated using 3-axis approaches, meaning that the tool axis is maintained parallel to the vertical axis. The 3-axis approach was justified using 3-axis CNC milling machines as the main technological equipment for SPIF. However, nowadays, the wide spreading of both 5-axis CNC milling machines and industrial robots, with far su…
COMPARATIVE ANALYSIS OF RIGID AND FLEXIBLE STRUCTURES OF THE ECCENTRIC PRESSES
Abstract The aim of this paper is to make a comparative study of the static behaviour of the eccentric presses, using the finite elements method, on the rigid structure and on the flexible structure, respectively. The finite elements modelling of the component elements of the presses are done in two ways: node by node link type (rigid structure) or using a linking element spring damper type (flexible structure). On these two structures there is successively applied a number of static analyses, in order to determine the strain of working area and the design of the stiffness graph.
Method for improving the contouring accuracy for CNC profiling machines at the shop floor level
Computer Numerically Controlled (CNC) laser cutting machines are capable of producing high-quality precise parts. However, as cutting speeds is increased, in order to achieve higher productivity, the accuracy of the parts is affected. In order to improve the contouring accuracy of these machines, a simple straight-forward joint simulation and experimental strategy is proposed. The position controllers within the feed drives are considered the key factor in improving the dynamic behavior and consequently the contouring accuracy of a CNC laser cutting machine at the shop floor level.
Researches regarding the reducing of burr size by optimising the cutting parameters on a CNC milling machine
This paper presents some experimental researches regarding burrs dimensions reduction that appear after the milling process together with an approach to reduce or eliminate the burrs resulted after this process. In order to reduce burrs dimensions, the milling process was executed with different cutting parameters and strategies then the results were evaluated.
Modular device for determining forming limit curves – a cost effective aproach
Abstract The paper presents the realising and functioning of a modular device for testing the formability of metal sheets. By using the device it is possible to realise experimentally the tests needed for drawing the forming limit curves using the Nakajima and Marciniak methods, but there can be also done researchs on deep-drawing. The results gathered from the tests were validated by numerical simulations using the finite element method. The device was designed at the Research Center for Metal Forming of the “Lucian Blaga” University of Sibiu and realised with the support of S.C. Uzina Mecanica Marsa – Sibiu