Abstract: The paper presents strength machine control system for characterization of fatigue properties of materials based on recently defined energy fatigue damage parameter under polyharmonic bending and torsion.
Abstract: The paper discusses the influence of ageing with sodium chloride water (3, 10, 20%) solutions on the destruction of epoxy coatings. The immersion of coatings in these media has caused the destruction of the coating surface in the form of cracks and increased roughness proportionally to the immersion period. The degree of surface destruction has increased along with the concentration of sodium chloride solution. Also, on the other hand, the inside structure of the coating has been subjected to changes that have occurred in the form of porosity growing with an increase in the ageing period.
Abstract: The article presents the research results referring to the analysis of the influence of finish treatment (finishing turning, grinding, burnishing) on the friction factor of steel applied to marine pump shafts. The research was performed on a roller 39 mm in diameter made of stainless steel 304L. The finish tooling of pump shaft pins was carried out on a universal centre lathe. The finish turning process was carried out by means of a WNMG WF 080408 Sandvik Coromant cutting tool with replaceable inserts. The grinding process was performed by grinding attachment for lathes. The 1 – 80×10×32 – 99C 80-N V grinding wheel was used for the process. The process of burnishing was done by SRMD burnishing tool by Yamato. The burnishing process could be carried out at the following technological parameters: burnishing force 1.1 kN, burnishing speed 35 m/min, feed 0.13 mm/rev [1, 2, 3]. The paper aimed at defining the influence of burnishing on service conditions by: testing electrochemical corrosion, friction wear and contact fatigue. The work presented the research results of friction factor tests of the samples after finish turning, grinding and burnishing. In addition, the influence of the burnisher passes number on the friction factor was determined. The experiment was performed on block – roll tester machine.
Abstract: Angular momentum pumps are very often applied on-board ships. These pumps are used in cooling circuits of medium and high power engines, power plant boilers and in bilge, ballast and fire installations. Very extensive use of angular momentum pumps on board is linked with their numerous advantages. During operation, the wear of the marine hull, the rotor and the shaft seals takes place. The research attempts to increase the service life of shafts. The article presents the research results referring to the analysis of the influence of finish treatment (turning, grinding and burnishing) on the corrosion properties of steel applied to marine pump shafts. The research was performed on a roller of 40 mm in diameter made of X5CrNi18-10 (AISI 304 L) stainless steel. The turning process was carried out by means of a WNMG WF 080408 Sandvik Coromant cutting tool with replaceable inserts. The grinding process was performed by grinding attachment for lathes. The 1 – 80×10×32 – 99C 80-N V grinding wheel was used for the process. The process of burnishing was done by SRMD burnisher from Yamato. In addition, the influence of the burnisher passes number on the corrosion properties was determined. The paper will present the results of electrochemical impedance spectroscopy and potentiodynamic research. To conduct the survey, the Atlas 0531 EU & IA potentiostat was used. Determination of the corrosion process parameters was performed by the computer programs: AtlasLab 2.0, EIS Spectrum Analyzer and Elfit2.
Abstract: The paper presents changes in UHMWPE morphology and structure caused by irradiation with an electron beam and plastic deformation. The input material consisted of two grades of polyethylene, i.e. GUR 1050 and GUR 1020 (Poly Hi Solidur Medi TECH), used for producing the bearing components of endoprostheses applied in total joint alloplasty. Tests involved three groups of samples: the ones subjected to modification through radiation (N) only, those modified by plastic deformation before (ON) and after (NO) irradiation with an electron beam (N). The obtained variants were subjected to comprehensive morphological and structural tests, which made it possible to document changes in the lamellar structure (SEM) and orientation of the crystalline structure (SAXS) as well as to determine the content of the crystalline phase (DSC) and to define crosslinking density.
Abstract: Materials with magnetic shape memory gained recognition for their greatest elongation in a group of smart materials, which reaches 10%; another advantage is high operating frequency. Disadvantages must also be considered, these are hysteresis, temperature sensitivity, other nonlinearities and high price. High strain makes it possible to use these materials in actuators design, but it is also possible to apply MSMA in energy harvesters and sensors. This article is linkage between physico-chemical R&D work and basic design of a transducer. Design of a test stand was described, different research scenarios were presented and to sum up this work graphs with the obtained results were placed.
Abstract: The present paper describes the results of the physicochemical and rheological characterisation of the selected self-made solutions of synthetic saliva. The substitutes of the used saliva were prepared on the basis of gums (xanthan, guar, arabic and carob bean) dissolved in saline buffer. Additionally, one of preparations were composed of xanthan gum and sodium dodecyl sulphate (SDS). The analysis of the viscosity, pH, surface tension and conductivity of the tested solutions was performed. The tests were carried out following one, three and seven days. The obtained results of the conducted studies showed differences between the tested preparations in the scope of the above evaluated quantities. The preparations based on the tested gums have similar properties in terms of pH, surface tension and conductivity. Only the substitute with the addition of xanthan gum and SDS exhibited different characteristics: the highest value of pH and the lowest values of conductivity and surface tension. In the case of viscosity, some preparations exhibited Newtonian rheological characteristics while others exhibited non-Newtonian characteristics.
Abstract: Modelling hysteresis curves is an important issue of research on soft magnetic materials. The paper presents the ideas of modelling the properties of soft magnets based on scaling analysis. The article describes in detail the application of the Widom scaling procedure for modelling energy losses and the coercive field of the Ni-Fe alloy and 6.5% Si-Fe steel. Finally, the results of scaling analysis and its possible advantages are discussed.
Abstract: Hysteresis modeling plays an important role for the designers of magnetic circuits. The paper considers the effect of processing temperature on magnetic properties of SMC cores. The hysteresis loops of the SMC cores are described using two recent modifications of phenomenological models.
Abstract: For the numerical analysis of TRIP steel wire drawing process, the Drawing 2d programme based of finite element method, has been used. The process was run following two variants, with small and large partial drafts for two drawing speeds: 1.11; 0.23 m/s. The investigations carried out allowed a relationship between temperature of drawing wires and the amount of retained austenite for wire surface and for wire axis.