Papers by Keyword: Surface

Abstract: As the external physical manifestation of the architecture, the material characteristics of the ecological building surface is that it is the most intuitive external carrier of its communication with people. On the premise of meeting the demand of energy efficiency, Ecological building should also produce a surface material expression form which resonates with peoples aesthetic needs, to achieve its unique aesthetic value.

Abstract: The effect of machined workpiece surface topography and surface integrity were studied. Modifications of surface layers after mechanical surface treatments were also reviewed. Conflict ideas exist in publications about which parameters can better define fatigue endurance. The traditional one was Arithmetic Average Roughness, although deepest surface feature and the square root of the defect area were proposed. The combinations of these factors including high temperature, metallurgical alternations and plastic deformations, rather than the residual stress alone affect surface topography and surface integrity. They should be examined carefully in order to gain a better understanding of fatigue.

Abstract: Epitaxial bilayer structure consisting of ferromagnetic (FM) metallic Pr_0.7Sr_0.3MnO₃ (PSMO) and antiferromagnetic (AFM) insulator La_0.5Ca_0.5MnO₃ (LCMO) was fabricated on (001)-oriented single crystal SrTiO₃ (STO) substrate by pulsed laser deposition technique. We studied the surface structure and interdiffusion at interface between PSMO and LCMO by using atomic force microscope and grazing incident x-ray reflectivity (GIXRR). The perfect data fitting result of GIXRR indicated that interdiffusion at the interface of Pr_0.7Sr_0.3MnO₃/La_0.5Ca_0.5MnO₃ (PSMO/LCMO) could not be negligible; there was a large interdiffusion zone at the PSMO/LCMO interfaces with a thickness of about 7 nm. We found that the thickness of the top layer at air/PSMO interface was about 2.5 nm and the mass density of the top layer was about 76.53% of that of PSMO layer. The surface roughness was about 1.6 nm which was consistent with observation by atomic force microscopy. Normal X-ray diffraction (NXRD) was also employed to investigate the average structure. Except from PSMO and LCMO layer diffraction peaks, we observed another additional peak, which was developed from the large disordered layer resulting from interdiffusion at the interface of PSMO/LCMO. This implied that the variation of crystalline structure of PSMO/LCMO film occurred due to interdiffusion. Surface roughness and interdiffusion played an important role in magnetic properties of FM/AFM bilayer.

Abstract: Due to the expansion of milling process with ball end mill in various branches of industry it became necessary for this process to be optimized. For this purpose it is necessary to identify the parameters that influence the process and establish their value for witch the results obtained to be the maximum in terms of qualitative and quantitative. Roughness of the surface machined can be considered as an important element that reflects the degree of successful optimization of this process. In order to solve the problems relating to the analysis and estimation of the surface roughness variation in ball end milling of C45 material with tool tilt angle, in this paper it was designed an experimental methodology followed by analysis of experimental data and estimation of surface roughness variation. The experimental research methodology presented in this paper can be extrapolated and used in a large number of processes.

Abstract: Parting surface design is the key to mold design. Taking mold design of a component as an example, this paper introduces the implementation of a parting surface design of complex multi-cavity mold supported by the surface technique of Pro/E software.

Abstract: The regularity of the erosion wear of a surface of a brittle polymeric material under the conditions of high-pressure (high-velocity) water-jet impact was examined using the atomic-force microscope. Investigations results proved that the elementary mechanism of erosive failure of brittle polymers in response to pressure and cyclic loads at micro and nanolevel may have brittle character, as well as elastoplastic and plastic character under severer regimes. The process of hardening of the fine (nanolevel) superficial layers of PMMA material has been determined in conditions of high-velocity water-drop loading.

Abstract: NiTi shape memory alloy is considered to be the most important shape memory alloys for its salient superelasticity and shape memory effect,which are displayed in martensitic transformations.In this paper, first-principles plane-wave method is utilized to systemically investigate the geometrical and electronic structures of NiTi (100) surface.Calculated the adsorption of oxygen atoms on the Ti/ NITI different location .The formation energy, Millikan population analysis results show that the Oxygen atoms easy to be adsorbed on the surface of Ti end surface,formation of TiO2.

Abstract: The paper presents a sample of wider set of new findings and recommendations from the area of the influence of technological parameters on the quality of surface of steel HARDOX 500 cut by AWJ technology and obtained by the evaluation of a large set of experiments within long-term activities of the Department of Manufacturing Processes Operation, Faculty of Manufacturing Technologies, Technical University in Košice, aimed at the diagnostics of operational states of manufacturing systems with AWJ technology.

Abstract: AlN dielectric thin films were deposited on N type Si(100) substrate by reactive radio frequency magnetron sputtering that directly bombardment AlN target under different sputtering-power and total pressure. The crystal structure,composition,surface and refractive index of the thin films were studied by XRD, SEM, AFM and elliptical polarization instrument. The results show that the surface and refractive of the thin films strongly depends on the sputtering-power and total pressure,the good uniformity and smoothness is found at 230 W, Ar flow ratio 5.0 LAr/sccm, substrate temperature 100°Cand 1.2 Pa. The crystal structure of the as-deposited thin-films is amorphous，then it transforms from blende structure to wurtzite structure as the rapid thermal annealing(RTA) temperature changes from 600 to 1200°C. The refractive index also increases with the RTA temperature it is increasing significantly from 800 to 1000°C．

Abstract: To study mobility limiting mechanisms in (0001) 4H-SiC, lateral n-channel MOSFETs in p-implanted wells on n-type epitaxial layers were manufactured and additionally selectively shallow implanted with different nitrogen (N) doses in the channel region. The mobility was found to be limited by Columbic scattering at low electric fields. Further surface roughness scattering was con-sidered as a possible mobility degradation mechanism at high electric fields. First investigations of the SiC surface by atomic force microscopy (AFM) in the channel region after implantation, anneal-ing, and gate oxide removal revealed a rather rough topology. This could lead to fluctuations in the surface potential at the SiC/SiO2 interface, thus accounting in part for surface roughness scattering.