Modern Machinery (MM) Science Journal, July 2012

EVALUATION OF MODERN POWER SOURCE FOR GMAW WELDING EQUIPPED WITH ADVANCED ARC CONTROL

L. Kolarik, M. Kolarikova, K. Kovanda, M. Pantucek, P. Vondrous
Keywords: Arc Control | Heat Input | Short Arc | Sequence Repeat | IAC | GMAW | Welding

Modern welding power sources are equipped with special functions of arc control. These functions measure and adjust welding parameters during welding with minimum time delay so that the right parameters are set. At the Laboratory of welding technologies of CTU in Prague we have used modern welding source by Migatronic – Sigma Galaxy equipped with functions Intelligent Arc Control and Sequence Repea (…)

IMPACT OF WATER REMAINS ON A HOT ROLLED PLATE AFTER COOLING

Radek Zahradnik
Keywords: ANSYS | rolling | hot plate | Simulation | FEA | water remains

In situations when a sheet metal plate with large dimensions is rolled, the water remains from cooling can be observed on the top site of the plate. This paper is focused on the deformations of the hot rolled sheet metal plate which are caused by the water remains after cooling. A transient finite element simulation was used to describe a shape deformations of a metal sheet cross profile. The finit (…)

MULTIPARAMETRIC ANALYSIS OF SURFACE INTEGRITY AFTER TURNING THROUGH BARKHAUSEN NOISE IN RELATION TO TOOL WEAR

Jaroslav Dubec, Miroslav Neslusan
Keywords: residual stress | tool wear | Barkhausen noise

This paper deals with application of micromagnetic inspection of surface integrity after turning bearing steel 100Cr6 in dependence on increasing tool wear. This paper indicates influence of tool wear on the selected parameters of Barkhausen noise (RMS value, peak position). The analysis also contains measurement of residual stresses carried out by mechanical method and also analysis of microstruct (…)

THE INFLUENCE OF HOLDING PRESSURE ON POWDER DISTRIBUTION IN PIM TECHNOLOGY

Pavel Petera
Keywords: Green part | Phase separation | Holding pressure | CIM | PIM

The powder injection molding technology (PIM) is very sensitive process where the resulting quality of the part is defined by quality reached in each step of the whole process. This quality of the part is then usually possible to see first at the end of the process while the fault could occur already at the beginning, often during injection-molding. Therefore is necessary to find the way how to ev (…)

STUDY OF AlSi10Mg ALLOY STRUCTURES AFTER MODIFICATION BY VARIOUS Sr AGENTS

Barbora Bryksi Stunova
Keywords: Structure Defects | Intermetallic Phases | Structure | Strontium | Modification | Aluminum Alloys

The goal of the paper was to observe structures of alloy AlSi10Mg, which was modified by strontium in amount of 400 ppm. It is widely known the influence of eutectic silicon, recent works describe also the influence on the morphology intermetallic phases, such as iron, manganese or copper containing phases. Present work focuses also to phases containing magnesium. The effect of strontium on the str (…)