MM Science Journal, March 2016

STUDY OF QUALITY OF NINE ALUMINIUM ALLOYS SURFACES CREATED USING ABRASIVE WATERJET

DAGMAR KLICHOVA, JIRI KLICH, LUCIE GURKOVA
Keywords: surface roughness | abrasive waterjet | study of quality | aluminium alloy | optical profilometer

The article focuses on the normalized method of measurement and evaluation of a surface texture created using the abrasive waterjet. It detects selected amplitude parameters of a roughness profile providing a form of a quantified description of properties of a surface topography. It studies the change in quality of machined surfaces created by the abrasive waterjet in nine selected materials of aluminiu (…)

LOAD TORQUE ANALYSIS OF INDUCTION MACHINE

MARTIN KROUPA, CESTMIR ONDRUSEK, ROSTISLAV HUZLIK
Keywords: induction machine | diagnosis | amplitude modulation | phase modulation | stator current signature | load torque oscillation | spectral analysis

This paper is focused on the load torque evaluation of the induction machine. There is described the problem of load torque oscillations and its impact to other electromagnetic variables in induction machine. In this article, the issue of modulated stator current is resolved and behaviors of amplitude and phase modulation are separated using demodulation algorithms after that. Newly, the variable load t (…)

METHODOLOGY OF HYDRAULIC SYSTEM DEVELOPMENT USING EXPERIMENTAL STAND AND COMPUTER MODELING

JOSEF NEVRLY, JAN BRANDEJS
Keywords: methodology | project | design | development | hydraulic | system

This paper deals with creation of methodology that can be effectively used in design and development of a more complex hydrostatic system. In future, the designed hydraulic system should fulfill given functions respecting the given parameters. It is usually possible to create such a system using several methods but not all of them lead to a full success without a risk of failure. It is not possible to (…)

ABRASIVES AND POSSIBILITIES OF INCREASE IN EFFICIENCY OF ABRASIVE WATERJETS

LIBOR SITEK, PETR MARTINEC
Keywords: high-speed waterjets | abrasive waterjets | abrasives | garnet | zirconia

The contribution focuses on the research into abrasive materials and possibilities of adjustment of their properties in order to increase the efficiency of the processes of cutting and machining with abrasive waterjets. Cutting ability of commonly available garnet concentrates and non-traditional products which are starting to access to the Czech market were tested and compared. In addition, entirely ne (…)

DUST FREE SURFACE TREATMENT PARAMETERS OF THE THREE-PHASE JET, GENERATED IN THE SANDBOT DEVICE

RYSZARD SOBCZAK, JAROSLAW PRAZMO, ANDRZEJ PEREC, IRENEUSZ CHMIELIK
Keywords: Three-phase jet | surface treatment | geometrical structure | dust free machining

This paper presents an original method for producing three-phase jet to enable efficient treatment of technical surface using the Sandbot apparatus. Exemplary results of studies describing the geometrical structure of machined surfaces in the context of their quality grading.The stream of three-phase (air-water-abrasive) generated in innovative Sandbot devices [Prazmo 2012] is a modern and high-performa (…)

HARDNESS AND ELASTICITY OF ABRASIVE PARTICLES MEASURED BY INSTRUMENTED INDENTATION

PAVOL HVIZDOS, MICHAL ZELENAK, SERGEJ HLOCH
Keywords: abrasive | garnet | Hardness | elasticity | instrumented indentation

Basic mechanical properties of seven types (from seven different sites) of abrasive garnet particles used for water jet cutting were measured using the technique of instrumented indentation (also called depth sensing indentation or nanoindentation). Hardness and modulus of elasticity were evaluated and compared. All the abrasives had similar measured mechanical properties (hardness 20 - 24.16 GPa), the (…)

INFLUENCE OF CHEMICAL COMPOSITION AND HEAT TREATMENT OF ALSI6CU4 ALLOY ON THE UTILIZATION OF COPPER STRENGTHENING EFFECTS

MARKO GRZINCIC
Keywords: Al-alloys | thermal treatment | hardening | intermetallic | Cu-phase

The paper presents deals with a quantification of intermetallic phases rich in copper in the alloy AlSi6Cu(X) with a variable content of copper, modified with strontium and during thermal treatment age hardening in artificial or natural way. It concerns variables occurring in the common industrial practice. The rate of solidification, thermal treatment regime and other elements of the alloy chemical com (…)

THE DESIGN AND SIMULATION OF THE SAFETY PART OF THE EXTRACTION SYSTEM OF THE HEAVY ION CYCLOTRON DC280 USING COMSOL MULTIPHYSICS

TOMAS MAAR, VLADIMIR I. KAZACHA
Keywords: thermal analysis | cyclotron | beam extraction system | COMSOL Multiphysics

This paper presents the design and thermal analysis using COMSOL Multiphysics® of safety part of the extraction system of the heavy ion cyclotron DC280. The heavy ion cyclotron DC280 was developed and is being constructed at the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research. High thermal power of the extracted beam is a risk of destruction for the elements of the bea (…)

APPLICATION OF RAPID PROTOTYPING TECHNOLOGY IN DESIGNING ROBOTS AND PERIPHERAL DEVICES

JAN LIPINA, VACLAV KRYS
Keywords: rapid prototyping | polycarbonate | Stratasys | bend tests | tensile tests | screw connection

The Department of Robotics at the Technical University of Ostrava has disposed of the Rapid Prototyping technology (hereinafter as RP) since 2009. From the very beginning, there were efforts to print not only models to present various concepts and prototypes to the public, but primarily functional technical solutions. Over the time, there have been a large number of printed parts as well as functional u (…)