Papers by Keyword: Steel Wire

Abstract: This article presents the development of energy-saving induction heating technology to accelerate significantly the process of heat treatment of steel wire. The analysis of international trends and prospects of the use of induction heating shows a steady expansion of the applied induction technologies in metallurgy. The article considers the advantages of induction heating in comparison with other competitive technologies. Heat treatment in electro-technical induction units is determined by the interrelated electrical and thermal processes in them, the complex nature of the distribution of internal heat sources, the dependence of the nature of the power distribution of the induction unit on the temperature of the products processed. The features of the applicated in the induction method of heating in the hardware industry for objects previously unused: such as coils of wire and riots of calibrated steel. The results of the study show the influence of the induction method of heating on temperature-time factors to the formation of the structure, to increase the uniformity of heating and the quality of heat treatment of steel wire, calibrated steel in riots, taking into account the technological problem. The authors give the assessment of the effectiveness of medium and high-frequency induction heating of steel wire of various diameters. The evaluation of the increase in the efficiency of an induction heating unit with the simultaneous heat treatment of several filaments of steel wire of the same diameter, combined into a bundle, was made.

Abstract: This article discusses the induction heating application features in metallurgical industry for previously unused objects, such as wire coils and wire rod bundles. The analysis of international trends and a forecast of the induction heating application shows a steady expansion of the induction technologies in the metallurgical industry. The article considers the advantages of induction heating in comparison to other competitive technologies. Heat treatment in electrotechnological induction plants is determined by the interconnected electric and thermophysical processes taking place in them, the complex nature of the internal heat sources distribution, the dependence of the distribution pattern of the induction plant on the temperature of the products being processed. It is shown that the investigation results of the induction heating method influence the temperature and time factors in the formation of the structure, the increase in the uniformity of heating, and the quality of the heat treatment of steel wire and wire rod buntle, taking into account the stated technological task. The efficiency estimation of application of medium and high-frequency induction heating of steel wire of various diameters is given. Evaluation of the efficiency improving of the induction heating device, when the heat treatment simultaneous multiple strands of steel wire of equal diameter, united in a bundle, is given.

Abstract: In view of the PC box girder transverse prestress tendon, the factors and the development of tension prestress performance affecting factors were analyzed. Experiment program of prestress tendon performance was designed. Test for steel wire and anchorage of transverse tendon were carried out. The performance data of steel strand and anchorage were tested. The transverse prestress steel beam pattern based on work performance test was analyzed.

Abstract: Steel wire-continuous basalt fiber composite plate (SBFCP) is a new type of plate whose main constituents are steel wire and basalt fiber reinforced polymer (BFRP). To investigate the mechanical properties of SBFCP, both theoretical and experimental studies were conducted. A tri-linear model was proposed to predict the stress-strain relationship of SBFCP. Considering two parameters, the volume ratio of steel wires in SBFCP and the type of composite pattern, a monotonic tensile experiment was carried out. Test results show that SBFCP has excellent properties, including high modulus, high strength, and good ductility. Results also demonstrate that the volume ratio of steel wires affects the modulus of SBFCP significantly whereas the type of composite pattern shows little effect on properties of SBFCP.

Abstract: In present research, the structure evolution of the pearlite steel wire during cold drawing is systematically investigated, and the relationship between structure evolution and strength increase during wire drawing is analyzed. During cold drawing, the wire strength increases; inter-lamellar spaces of the pearlites decrease, which has an important effect on properties of cold drawn wires; accumulation of high density dislocation in ferrite phase can be thought to be one of the reasons for strengthening the wire, meanwhile, the amorphous phase forming in cemetites also make the wire strengthen; especially, the wire strength is effected seriously by the intensity of the fiber texture <110>, and as drawing, the wire strength increases.

Abstract: The normal stress between wires is one of the main factors of the slipping and stress concentration in the stay-cables. In order to improve the research on the stay-cables, the mechanism of the normal stress has been studied in this paper. The normal stress can be resulted from two reasons. Firstly, the normal stress generate from the semi-parallel wires because of the existence of spiral angle. Secondly, the normal stress results from the pinch-effect generated by the hot-extruding PE protection. Both the formulation have been listed to analyse the normal stress in this paper. Result shows, the normal stress between the outermost layers is far smaller than the inner layers. Finally, the field survey surveys have been used to verify the analysis.

Abstract: An experimental investigation was carried out to braze diamond abrasives onto thin steel wires, in which case the brazing was conducted in the vacuum and under high temperatures by using a nickel-based powder as brazing alloy. The morphologies and microstructures of the brazed wires were observed and the comprehensive mechanical properties of the brazed wires were tested. The brazed wires were also used to cut such brittle materials as ceramics, glass, and natural stone. It is shown that a typical phenomenon of brazing alloy’s climbing around the diamond grains was observed in brazing the wires. Through observing the cross-section of brazed wires, it is observed that there is a good bonding between the brazing alloy and the body of steel wires. The crystal grains of the steel wires grew significantly after brazing. Through observing the morphologies of the diamond wires and the surfaces of four workpiece materials, few diamond pull-outs were found on the wires and the kerfs on the workpiece materials were basically flat.

Abstract: In this paper, torsion fracture behavior of drawn pearlitic steel wires with different heat treatments was investigated. Samples with different heat treatment conditions were subjected to torsion and tensile tests. The shear strain along the torsion sample after fracture was measured. Fracture surface of wires was examined by Scanning Electron Microscopy. In addition, the method of Differential Scanning Calorimetry was used to characterize the thermodynamic process in the heat treatment. A numerical simulation via finite element method on temperature field evolution for the wire during heat treatment process was performed. The results show that both strain aging and recovery process occur in the material within the temperature range between room temperature and 435 °C. It was shown that the ductility measured by the number of twists drops at short heating times and recovers after further heating in the lead bath of 435 °C. On the other hand, the strength of the wire increases at short heating times and decreases after further heating. The microstructure inhomogeneity due to short period of heat treatment, coupled with the gradient characteristics of shear deformation during torsion, results in localized shear deformation of the wire. In this situation, shear cracks nucleate between lamella and the wire breaks with low number of twists.

Abstract: The residual stress in axial direction of the steel wires has been measured by using a method based on the combination of the focused ion beam (FIB) milling and digital image correlation (DIC) program. The residual stress is calculated from the measured displacement field before and after the introduction of a slot along the steel wires. The displacement is obtained by the digital correlation analysis of high-resolution scanning electron micrographs, while the slot is introduced by FIB milling with low energy beam. The experimental procedures are described and the feasibilities are demonstrated in steel wires fabricated with different conditions.