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Vibratory equipment is widely used for performing various finishing processes, machining and forcing of different parts and materials. Numerous researchers and technologists pay specific attention to the possibilities of implementing vibration-driven machinery for conducting the lapping and polishing operations on flat surfaces. The present paper is dedicated to studying the laps kinematic parameters of the vibratory finishing machine actuated by six electromagnets. The paper's scientific novelty consists in the experimental verification of the previously modelled and simulated circular trajectories of the laps under different operational conditions. The methodology of research contains two basic stages: changing the excitation frequency at the constant traction force and changing the traction force at the constant excitation frequency. The improved 3D-design of the vibratory finishing machine was developed in the SolidWorks software. The experimental prototype was implemented in practice, and full-scale tests were carried out using the WitMotion sensors and software. Based on the obtained experimental data, the trajectories of the machine's laps were constructed and analyzed in the MathCad software. The research results substantiate the possibilities of providing circular oscillations of the laps at different operational conditions. The results can be used by technologists and engineers while choosing the appropriate design and control parameters for similar vibratory equipment intended for lapping and polishing of flat surfaces. [ABSTRACT FROM AUTHOR]

The traditional manufacturing industry has been revolutionized with the introduction of additive manufacturing which is based on layer-by-layer manufacturing. Due to these tool-free techniques, complex shape manufacturing becomes much more convenient in comparison to traditional machining. However, additive manufacturing comes with its inherent process characteristics of high surface roughness, which in turn effect fatigue strength as well as residual stresses. Therefore, in this paper, common post-processing techniques for additive manufactured (AM) parts were examined. The main objective was to analyze the finishing processes in terms of their ability to finish complicated surfaces and their performance were expressed as average surface roughness (Sa and Ra). The techniques were divided according to the materials they applied to and the material removal mechanism. It was found that chemical finishing significantly reduces surface roughness and can be used to finish parts with complicated geometry. Laser finishing, on the other hand, cannot be used to finish intricate internal surfaces. Among the mechanical abrasion methods, abrasive flow finishing shows optimum results in terms of its ability to finish complicated freeform cavities with improved accuracy for both polymer and metal parts. However, it was found that, in general, most mechanical abrasion processes lack the ability to finish complex parts. Moreover, although most of post-processing methods are conducted using single finishing processes, AM parts can be finished with hybrid successive processes to reap the benefits of different post-processing techniques and overcome the limitation of individual process. [ABSTRACT FROM AUTHOR]

Surface integrity induced by finishing processes significantly affects the functional performance of machined components. In this work, three kinds of finishing processes, i.e., precision hard turning, conventional grinding, and sequential grinding and honing, were used for the finish machining of AISI 52100 bearing steel rings. The surface integrity induced by these finishing processes was studied via SEM investigations and residual stress measurements. To investigate rolling contact fatigue performance, contact fatigue tests were performed on a twin-disc testing machine. As the main results, the SEM observations show that precision hard turning and grinding introduce microstructural alterations. Indeed, in precision hard turning, a fine white layer (<1 μm) is observed on the top surface, followed by a thermally affected zone in the subsurface, and in grinding only, a white layer with 5 μm thickness is observed. However, no microstructural changes are found after sequential grinding and honing processes. White layers induced by precision hard turning and grinding possess compressive residual stresses. Grinding and sequential grinding and honing processes generate similar residual stress distributions, which are maximum and compressive at the machined surface and tensile at the subsurface depth of 15 μm. Precision hard turning generates a "hook"-shaped residual stress profile with maximum compressive value at the subsurface depth and thus contributes as a prenominal factor to the obtainment of the longest fatigue life with respect to other finishing processes. Due to the high quality of surface roughness (Ra = 0.05 μm), honing post grinding improves the fatigue life of bearing rings by 2.6 times in comparison with grinding. Subsurface compressive residual stresses, as well as low surface roughness, are key parameters for extending bearing fatigue life. [ABSTRACT FROM AUTHOR]

Copyright of Industria Textila is the property of Institutul National de Cercetare-Dezvoltare pentru Textile si Pielarie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Due to "insensibilis perspiration" process of the human body, the textile materials for the garment products, must have vapour permeability. In order to feel the thermo physiological comfort during clothing wear, the vapour permeability values must be correlated with the environment, the body conditions and factor related to the fabrics (finishing treatments, structure, raw materials).Vapour permeability capacity through fabrics are important properties of fabrics that influence the comfort of thermo-physiological products for apparel products. Chemical finishing processes applied to textile materials can improve or reduce the vapour permeability capability depending on the destination. Textile dyeing and film finishing processes influence the vapour permeability and implicitly, the other thermophysiological comfort features (air permeability, thermal insulation) that determine the use of a textile fabric.The paper presents the results of the researches realized on samples of fabrics with different structures, made from polyester yarns in the warp system, with different length densities. The purpose of the research is to emphasize the influence of chemical finishing processes (dyeing and waterproofing through film coating) on vapour permeability values. The experimental values obtained for vapour permeability as well as the calculated coefficients of vaporization, as a direct indicator of this thermo physiological comfort feature, have allowed the determination of the range of use of the analysed fabrics.

The traditional manufacturing industry has been revolutionized with the introduction of additive manufacturing which is based on layer-by-layer manufacturing. Due to these tool-free techniques, complex shape manufacturing becomes much more convenient in comparison to traditional machining. However, additive manufacturing comes with its inherent process characteristics of high surface roughness, which in turn effect fatigue strength as well as residual stresses. Therefore, in this paper, common post-processing techniques for additive manufactured (AM) parts were examined. The main objective was to analyze the finishing processes in terms of their ability to finish complicated surfaces and their performance were expressed as average surface roughness (Sa and Ra). The techniques were divided according to the materials they applied to and the material removal mechanism. It was found that chemical finishing significantly reduces surface roughness and can be used to finish parts with complicated geometry. Laser finishing, on the other hand, cannot be used to finish intricate internal surfaces. Among the mechanical abrasion methods, abrasive flow finishing shows optimum results in terms of its ability to finish complicated freeform cavities with improved accuracy for both polymer and metal parts. However, it was found that, in general, most mechanical abrasion processes lack the ability to finish complex parts. Moreover, although most of post-processing methods are conducted using single finishing processes, AM parts can be finished with hybrid successive processes to reap the benefits of different post-processing techniques and overcome the limitation of individual process.

For the sustainability of continuous improvement, the importance of acquiring as much data as possible from the production field is indisputable. However, converting these data into key performance indicators in a lean production system is much more important. This paper focuses on the finishing processes of the weaving industry in a real production plant. In the study, roll of fabric based traceability is first provided by a radio frequency identification (RFID) and programmable logic controller (PLC) automation structure. In the next step, the calculation of the overall equipment effectiveness (OEE) for each process is provided, and a method of converting these OEE values to the unique indicator as the overall throughput effectiveness (OTE) is proposed. In the last phase of the paper, after getting OTE value automatically, it was aimed to reveal the relationship between the production environment parameters and the OTE indicator. A revised hybrid genetic algorithm was proposed to determine the most important production environment parameters that affect OTE results. Multiple linear regression was utilized to verify the result of the developed algorithm. [ABSTRACT FROM AUTHOR]

Abstract This study compares gear surface characteristics generated by grinding, honing and superfinishing of case-hardened steel, including the evolution during efficiency testing with two different prior running-in loads (0.9 GPa and 1.7 GPa). The most influential factor was surface roughness. Micro-pitting was associated with surface asperities and hence only seen in ground and honed gears, while being absent for super-finished gears. The micro-pitting was enhanced by running-in load, but only for rough surfaces. Deformation-induced localized microstructure impact was associated with cracks. Residual stresses reached similar levels after efficiency testing. Phosphorous content in the gear surface was connected to surface roughness and running-in load. Highlights • The most influential surface characteristic was roughness. • Running-in load influenced the evolution of surface characteristics and micropitting, but only for rough surface. • Deformation induced localized bands confined to < 7µm were found to be in connection with the cracks. • The variation in residual stresses between as-manufactured conditions is associated with retained austenite content. • The phosphorous content in the gear surface was enhanced by the roughness and running-in load. [ABSTRACT FROM AUTHOR]

Due to "insensibilis perspiration" process of the human body, the textile materials for the garment products, must have vapour permeability. In order to feel the thermo physiological comfort during clothing wear, the vapour permeability values must be correlated with the environment, the body conditions and factor related to the fabrics (finishing treatments, structure, raw materials). Vapour permeability capacity through fabrics are important properties of fabrics that influence the comfort of thermo-physiological products for apparel products. Chemical finishing processes applied to textile materials can improve or reduce the vapour permeability capability depending on the destination. Textile dyeing and film finishing processes influence the vapour permeability and implicitly, the other thermophysiological comfort features (air permeability, thermal insulation) that determine the use of a textile fabric. The paper presents the results of the researches realized on samples of fabrics with different structures, made from polyester yarns in the warp system, with different length densities. The purpose of the research is to emphasize the influence of chemical finishing processes (dyeing and waterproofing through film coating) on vapour permeability values. The experimental values obtained for vapour permeability as well as the calculated coefficients of vaporization, as a direct indicator of this thermo physiological comfort feature, have allowed the determination of the range of use of the analysed fabric [ABSTRACT FROM AUTHOR]

The production of parts by additive manufacturing technologies is a hot topic for industry. The Selective Laser Melting process is among the most widely used nowadays. Unfortunately the geometrical accuracy, as well as the surface roughness are very poor. Functional surfaces therefore require further machining operations in order to fulfill the specifications of the designer. However the influence of finishing operations on the surface integrity of such parts needs to be further investigated. This paper aims at analyzing the influence of milling or polishing operations on the rotary bending fatigue resistance of titanium samples generated by SLM. It is highlighted that finishing operations are able to improve significantly the fatigue resistance compared to the initial state after SLM + heat treatment. The fatigue results are also discussed in light of the surface integrity (roughness parameters and residual stresses). It is found that the surface topography skewness is an interesting parameter which correlates with the fatigue performance. None of these finishing techniques are able to lead to a fatigue resistance comparable to the one obtained with a wrought titanium part. [ABSTRACT FROM AUTHOR]

Micro geometry of a gear tooth influences the contact durability and wear performance. In this paper, different gear tooth flanks have been manufactured by different finishing processes, which were then characterized using multiscale surface analysis, based on wavelet transform. The friction noise was then measured before and after meshing in dry and lubricated conditions, to quantify the acoustic performance of the surfaces. To accomplish this objective, a new non-destructive sensory measurement technique was developed to characterize the friction noise generated by teeth flank surface. Results show the ability of the new method to discriminate functional behavior of different surfaces as well as give possible explanations as to the contribution of tooth flank asperities during the meshing on the gear in terms of gear noise performances. [ABSTRACT FROM AUTHOR]

The contribution of gear tooth flank surface micro-finish on gear noise has not yet been taken into consideration. This paper is devoted to study the simultaneous effect of tooth roughness and lubricant viscosity on automotive gear vibrations. The vibrations performances were evaluated on an instrumented test rig under both dry and wet conditions. A non-destructive replication technique coupled to 3D optical measures was used to acquire the flanks topographies, which were characterized using multiscale decomposition. A three-dimensional finite element simulation of a helical gear was performed to assess the micro-scales impact on gear noise. Numerical representative surfaces morphologies were introduced into the simulation and compared through the transmission error calculation. Results have shown gear noise dependence on tooth finishing processes. [ABSTRACT FROM AUTHOR]

Frequently, strict conditions are imposed for high precision components manufacture such as high dimensional precision, accurate geometrical form and good surface finish. High precision machining allows industry to dispense with successive operations such as turning, grinding and polishing to attain these objectives. In this paper, precision hard turning is proposed for the finishing of AISI 52100 bearing components. Several developments were carried out on the prototype lathe in order to adapt it to machining hard steel AISI 52100. To ensure high stability and stiffness during machining, the performances of hydrostatic X and Z-axis slides-ways were investigated. Machined surfaces were characterized in terms of roughness, microstructure analysis, quantitative phase composition and residual stress measurements. The achieved surface roughness R a is in the range of 0.1–0.2 μm. Microstructural investigations revealed metallurgical transformations, such as the presence of a very fine white layer (<1 μm) on the top surface and a thermal affected zone (transition zone) of 35–50 μm in the sub-surface. Energy dispersive X-ray diffraction analyses show that the percentage of the different phases is not quantitatively affected and the material remains in the martensite phase. X-ray measurements show that Full Width at Half-Maximum (FWHM) is lower in the transition zone than in the bulk material. This decrease of FWHM may be associated to a decrease of dislocation rate. Precision hard turning induces compressive residual stresses at the surface and in the subsurface, which corresponds to the transition zone. Moreover, increasing cutting speed leads to increase the level of compressive residual stresses. [ABSTRACT FROM AUTHOR]

Copyright of Exacta is the property of Exacta - Engenharia de Producao and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Fibres & Textiles in Eastern Europe is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The appearance and hand of end-use fabrics has become more and more important when purchasing textile fabrics. The finishing parameters have complex influences on the large number of changes that occur in fabric properties during finishing processes. This study focused on the influences of different finishing parameters on mechanical and surface properties in order to discover the most appropriate finishing process according to the requirements of fabric handle and appearance. The KES-F system was used to evaluate fabric hand objectively, as well as the mechanical and surface properties of a woven wool fabric. Four finishing processes were selected, which differed in relation to the temperature when drying (T1=160 °C, T2=180 °C) and processing conditions during autoclave decatizing (T1=95 °C, p1=0.4 bar, T2=110 °C, p2=1 bar). The effect of the influential parameters inside four different finishing processes on the mechanical properties and hand of a selected woven fabric was evaluated using the analysis of variance. The results show that tensile properties are much more influenced by the belt pressing process while bending and shear properties are influenced by continuous decatizing process, which is the process that mostly improves fabric stability at the beginning of the dry finishing cycle. When the primary and total hand values were observed, it could be seen that applying chemicals during belt pressing had some consequences, the impacts of which could be observed directly in the resulting hand values. [ABSTRACT FROM AUTHOR]

A new finishing process that uses magnetic force with high efficiency to assist discharging dregs from the electrode gap during electrochemical finishing on freeform surfaces is investigated in the current study. The factors affecting electrochemical finishing and the effects of magnetic assistance are primarily discussed. The main experimental parameters are magnetic strength, distance between the two magnets, diameter of the electrode, current density, the on/off period of pulsed current, and rotational speed of the wire electrode. Providing a large magnetic field intensity or using a smaller distance between the two magnets produces a larger magnetic force and discharge efficiency, and results in a better finish. A higher current density with magnetic assistance reduces the finishing time and avoids difficulties in dreg removal. A high rotational speed of the wire electrode produces a better finish. Pulsed direct current can slightly promote the effect of electrochemical finishing, but the current density needs to be higher. Magnetic assistance during the electrochemical finishing process makes a greater contribution in a shorter time making the surface of the workpiece smooth and bright. [ABSTRACT FROM AUTHOR]

This article examines the surface qualities of textile objects in the 1880 to 1939 period, analyzing representations and descriptions of both highly finished and maintained textile surfaces, and degraded and ill-maintained garments. It is argued that the finishing techniques applied in manufacture were carefully replicated in domestic processes, and that qualities of surface and finish in textiles were important both materially and symbolically in the stratified social systems of late nineteenth- and early twentieth-century Britain. Theoretical insights from Julia Kristeva and Mary Douglas are used to understand the meanings of textile objects in use and wear, in their relationship to the bodies that wore them, and in the processes of maintenance to which they were subjected. [ABSTRACT FROM AUTHOR]

The growing use of contemporary materials in various industrial sectors, such as aerospace, automotive, as well as the oil and gas industry, requires appropriate machining methods and tools. Currently, apart from the necessity to obtain high-dimensional and shape accuracy, the efficiency and economic aspects of the selected manufacturing process are equally important, especially when difficult-to-cut materials, such as hard and brittle ceramics, have to be machined. In the research presented in this paper, a prototype tool fabricated from polyamide powder by the SLS method was used in flat-lapping of Al2O3 ceramics, showing the promising potential and efficacy of rapid tooling and manufacturing in the area of abrasive machining. The influence of the selected input process factors, such as machining time, the type of abrasive suspension, kinematic parameters, and unit pressure, on technological effects, was analyzed. The microscopic observations of the active surface of the prototype tool showed its reinforcement with loose diamond abrasive particles (size D107), resulting in the effective material removal and improved surface finish of Al2O3 ceramic samples. The directions for further development of tools fabricated by the SLS method for applications in abrasive machining were also envisaged by the authors. [ABSTRACT FROM AUTHOR]

Nowadays, improvement of the surface finish of parts manufactured by fused deposition modelling is a well-studied topic. Chemical post-treatments have proven to be the best technique in terms of time consumption and smoothness improvement. However, these treatments modify the structure of the material and, consequently, its mechanical properties. This relationship was studied in this work. In this case, on the basis of a previous study on crystallisation, polylactic acid pieces were subjected to different post-treatments to evaluate their effects on the sample's mechanical properties, i.e., tensile strength and hardness. Models were obtained according to their percentage of crystallisation, which was related to the different treatments, as well as immersion time. Dramatic changes were obtained within a wide range of material behaviour with some treatments. Specifically, changes were obtained in the maximum stress (from 55 to 20 MPa), in elongation (from 3% to 260%), and in the hardness scale (Shore D to A). [ABSTRACT FROM AUTHOR]

The application of techniques to improve the surface finish of pieces obtained by fused deposition modelling, as well as other functional aspects, is of great interest nowadays. Polylactic acid, a biodegradable material, has been considered a possible substitute for petroleum-based polymers. In this work, different chemical post-processing methods are applied to polylactic acid pieces obtained by fused deposition modelling and some characteristics are studied. Structural, thermal, and crystallinity property changes are analyzed according to the treatments applied. This can prevent degradation, eliminate the glass transition phase of the material, and thereby increase the thermal resistance by about 50 °C. An improvement in the roughness of the pieces of up to 97% was also found. [ABSTRACT FROM AUTHOR]