Hard Protective Layers on Forging Dies—Development and Applications

The article presents a summary of many years of activities in the area of increasing the durability of forging dies. The results of comprehensive research work on the analysis of the destructive mechanisms of forging dies and the possibility of increasing their durability with the use of modern surface engineering methods are presented. Great possibilities in terms of shaping operational properties of forging dies by producing hybrid layers of the “Nitrided Layer + PVD Coating” (NL + PVD coating) type were confirmed. An analysis of changes in forging dies durability under various operating conditions was performed, i.e., forging—die—forging press—pressures. It has been shown that the variety of parameters of the forging process, including forgings’ geometry and weight, materials, precision, pressures applied, and, what is very important, quality of machines, makes it very difficult to compare the effectiveness of various PVD coating solutions in the process of increasing the durability of forging dies. Hybrid layers of the “NL + PVD coating” type create great possibilities in shaping the operational properties of tools and machine elements. However, in each application a precise diagnosis of the wear mechanism and the design of an individual PVD coating material solution is required.

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Mechanisms for the Transfer of Innovative Surface Engineering Solutions to Industrial Practice on the Example of Hybrid Layers

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.237.54 ◽

2015 ◽

Vol 237 ◽

pp. 54-60

Author(s):

Adam Mazurkiewicz ◽

Jerzy Smolik ◽

Beata Poteralska

Keyword(s):

Surface Engineering ◽

Technological Development ◽

Nitrided Layer ◽

Rapid Development ◽

Hot Forging ◽

Hybrid Layer ◽

Industrial Practice ◽

Coated Materials ◽

Application Requirements ◽

Hybrid Layers

Advanced surface engineering technologies are the basis of the intense technological development in the world over the past several decades. The rapid development of surface engineering resulted in the appearance of many new top layer solutions, such as multi-layer coatings, nanostructured coatings, and hybrid layers, which prove to be very effective in their applications. The production of layers and coatings with complex microstructure and application requirements (related to coated materials, the geometry of the engineered elements, economic viability) create a need for advanced technological and organizational solutions.This article presents a technology of manufacturing a hybrid layer: “nitrided layer + (Cr/CrN) multilayer,” intended to increase the durability of hot forging dies. Based on this example, those surface engineering fields are presented where simultaneous intensive development is necessary to ensure an efficient process of transferring innovative surface engineering solutions to the industry.

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Energetic and exergetic analysis of a convective drier: A case study of potato drying process

Open Agriculture ◽

10.1515/opag-2020-0058 ◽

2020 ◽

Vol 5 (1) ◽

pp. 563-572

Author(s):

Iman Golpour ◽

Mohammad Kaveh ◽

Reza Amiri Chayjan ◽

Raquel P. F. Guiné

Keyword(s):

Energy Consumption ◽

Research Work ◽

Specific Energy Consumption ◽

Exergy Efficiency ◽

Operating Conditions ◽

Energy Utilization ◽

Convective Drying ◽

Drying Time ◽

Energy And Exergy ◽

Exergy Losses

AbstractThis research work focused on the evaluation of energy and exergy in the convective drying of potato slices. Experiments were conducted at four air temperatures (40, 50, 60 and 70°C) and three air velocities (0.5, 1.0 and 1.5 m/s) in a convective dryer, with circulating heated air. Freshly harvested potatoes with initial moisture content (MC) of 79.9% wet basis were used in this research. The influence of temperature and air velocity was investigated in terms of energy and exergy (energy utilization [EU], energy utilization ratio [EUR], exergy losses and exergy efficiency). The calculations for energy and exergy were based on the first and second laws of thermodynamics. Results indicated that EU, EUR and exergy losses decreased along drying time, while exergy efficiency increased. The specific energy consumption (SEC) varied from 1.94 × 105 to 3.14 × 105 kJ/kg. The exergy loss varied in the range of 0.006 to 0.036 kJ/s and the maximum exergy efficiency obtained was 85.85% at 70°C and 0.5 m/s, while minimum exergy efficiency was 57.07% at 40°C and 1.5 m/s. Moreover, the values of exergetic improvement potential (IP) rate changed between 0.0016 and 0.0046 kJ/s and the highest value occurred for drying at 70°C and 1.5 m/s, whereas the lowest value was for 70°C and 0.5 m/s. As a result, this knowledge will allow the optimization of convective dryers, when operating for the drying of this food product or others, as well as choosing the most appropriate operating conditions that cause the reduction of energy consumption, irreversibilities and losses in the industrial convective drying processes.

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Different Techniques to Mitigate Partial Shading in Photovoltaic Panels

Energies ◽

10.3390/en14133863 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3863

Author(s):

Tiago Alves ◽

João Paulo N. Torres ◽

Ricardo A. Marques Lameirinhas ◽

Carlos A. F. Fernandes

Keyword(s):

Cell Model ◽

Research Work ◽

Experimental Tests ◽

Operating Conditions ◽

Pv System ◽

Partial Shading ◽

System Architectures ◽

Pv Systems ◽

Advantages And Disadvantages ◽

Pv Panel

The effect of partial shading in photovoltaic (PV) panels is one of the biggest problems regarding power losses in PV systems. When the irradiance pattern throughout a PV panel is inequal, some cells with the possibility of higher power production will produce less and start to deteriorate. The objective of this research work is to present, test and discuss different techniques to help mitigate partial shading in PV panels, observing and commenting the advantages and disadvantages for different PV technologies under different operating conditions. The motivation is to contribute with research, simulation, and experimental work. Several state-of-the-artsolutions to the problem will be presented: different topologies in the interconnection of the panels; different PV system architectures, and also introducing new solution hypotheses, such as different cell interconnections topologies. Alongside, benefits and limitations will be discussed. To obtain actual results, the simulation work was conducted by creating MATLAB/Simulink models for each different technique tested, all centered around the 1M5P PV cell model. The several techniques tested will also take into account different patterns and sizes of partial shading, different PV panel technologies, different values of source irradiation, and different PV array sizes. The results will be discussed and validated by experimental tests.

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Agglomeration Technologies of Processing Powder Wastes

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.244.121 ◽

2015 ◽

Vol 244 ◽

pp. 121-129

Author(s):

Marian Peciar ◽

Roman Fekete ◽

Peter Peciar

Keyword(s):

Research Work ◽

Operating Conditions ◽

Airborne Particles ◽

Raw Material ◽

Production Cycle ◽

Shear Forces ◽

Material Resources ◽

New Type ◽

Two Phases ◽

High Technologies

This article deals with the presentation of modern applications for processing powdered, primarily hazardous, waste to an agglomeration form appropriate for subsequent processing by classical methods, for example in the construction, automotive and consumer goods industries. The aim of the research work was to set appropriate operating conditions in order to appreciate currently non-processable wastes resulting from the intensive production of often extremely expensive materials. Technologies which enable returning powder waste back into the primary production cycle were developed and experimentally tested, thus saving raw material resources. When necessary for the fixing of fine airborne particles with a problematic compacting curve (hard to compress, repulsive due to the surface charge) extrusion processes using a patented technology enabling controlled modification of shear forces in the extrusion zone were successfully applied. A new type of axial extruder allows the elimination of the liquid phase and as a result prevents the clogging of the extrusion chamber. In the case of need for granulation of sensitive materials (for example pharmaceuticals not allowing the addition of any kind of agglomerating fluid or reacting strongly in the contact of the two phases), a process of compaction between rolls with different profiled surface was successfully applied. The developed high technologies and the resulting products thus represent a major contribution to environmental protection in the context of not only the work but also the communal environment.

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A Novel Decarburizing-Nitriding Treatment of Carburized/through-Hardened Bearing Steel towards Enhanced Nitriding Kinetics and Microstructure Refinement

Coatings ◽

10.3390/coatings11020112 ◽

2021 ◽

Vol 11 (2) ◽

pp. 112

Author(s):

Fuyao Yan ◽

Jiawei Yao ◽

Baofeng Chen ◽

Ying Yang ◽

Yueming Xu ◽

...

Keyword(s):

Surface Engineering ◽

Plasma Nitriding ◽

Nitrided Layer ◽

Metallographic Analysis ◽

Material Surface ◽

Low Carbon ◽

High Carbon ◽

Softening Effect ◽

Microstructure Refinement ◽

Bearing Steels

Decarburization is generally avoided as it is reckoned to be a process detrimental to material surface properties. Based on the idea of duplex surface engineering, i.e., nitriding the case-hardened or through-hardened bearing steels for enhanced surface performance, this work deliberately applied decarburization prior to plasma nitriding to cancel the softening effect of decarburizing with nitriding and at the same time to significantly promote the nitriding kinetics. To manifest the applicability of this innovative duplex process, low-carbon M50NiL and high-carbon M50 bearing steels were adopted in this work. The influence of decarburization on microstructures and growth kinetics of the nitrided layer over the decarburized layer is investigated. The metallographic analysis of the nitrided layer thickness indicates that high carbon content can hinder the growth of the nitrided layer, but if a short decarburization is applied prior to nitriding, the thickness of the nitrided layer can be significantly promoted. The analysis of nitriding kinetics shows that decarburization reduces the activation energy for nitrogen diffusion and enhances nitrogen diffusivity. Moreover, the effect of decarburization in air can promote surface microstructure refinement via spinodal decomposition during plasma nitriding.

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Composite Layers “MgAl Intermetalic Layer / PVD Coating” Obtained On The AZ91D Magnesium Alloy By Different Hybrid Surface Treatment Methods

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0255 ◽

2015 ◽

Vol 60 (2) ◽

pp. 1031-1035 ◽

Cited By ~ 4

Author(s):

J. Smolik ◽

A. Mazurkiewicz ◽

J. Kacprzyńska-Gołacka ◽

M. Rydzewski ◽

M. Szota ◽

...

Keyword(s):

Surface Treatment ◽

Magnesium Alloys ◽

Surface Engineering ◽

Composite Layer ◽

Electron Beam Evaporation ◽

Treatment Technology ◽

Corrosion Properties ◽

Pvd Coating ◽

Composite Layers ◽

Coating Composite

Abstract Magnesium alloys have very interesting physical properties which make them ‘materials of the future’ for tools and machine components in many industry areas. However, very low corrosion and tribological resistance of magnesium alloys hampers the implementation of this material in the industry. One of the methods to improve the properties of magnesium alloys is the application of the solutions of surface engineering like hybrid technologies. In this paper, the authors compare the tribological and corrosion properties of two types of “MgAlitermetalic / PVD coating” composite layers obtained by two different hybrid surface treatment technologies. In the first configuration, the “MgAlitermetalic / PVD coating” composite layer was obtained by multisource hybrid surface treatment technology combining magnetron sputtering (MS), arc evaporation (AE) and vacuum heating methods. The second type of a composite layer was prepared using a hybrid technology combined with a diffusion treatment process in Al-powder and the electron beam evaporation (EB) method. The authors conclude, that even though the application of „MgAlitermetalic / PVD coating” composite layers can be an effective solution to increase the abrasive wear resistance of magnesium alloys, it is not a good solution to increase its corrosion resistance.

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Knowledge management of automobile system failures through development of failure knowledge ontology from maintenance experience

Journal of Advances in Management Research ◽

10.1108/jamr-02-2017-0024 ◽

2017 ◽

Vol 14 (4) ◽

pp. 425-445 ◽

Cited By ~ 3

Author(s):

Ajith Tom James ◽

O.P. Gandhi ◽

S.G. Deshmukh

Keyword(s):

Knowledge Management ◽

Service Providers ◽

Research Work ◽

Data Entry ◽

Operating Conditions ◽

Service Experience ◽

Content Type ◽

System Failures ◽

Explicit Consideration ◽

Ontological Model

Purpose The purpose of this paper is to develop an ontological model of failure knowledge of automobile systems that will enhance the knowledge management of automobile system failures, which will help for design and maintenance of automobiles. Failure knowledge of automobile systems and components gained through maintenance and repair can mitigate future failures, if integrated in the design. This is an outcome of this paper. Design/methodology/approach A failure coding scheme is developed for assimilating various entities of automobile failure knowledge and an ontological model is developed for its systematic structuring and representation. The developed failure code is a combination of alphanumeric and numeric code that incorporates ingredients of the failure knowledge, which will help database management, with reduced data entry time and storage space. Findings The maintenance of automobiles not only brings back the systems into operating conditions but also convey a lot of information regarding the failures. This is a useful input to the designers in development of reliable and maintainable automobile systems. A knowledge base can be created for automobile systems/components failures from their maintenance and service experience. Research limitations/implications Developed ontological model of automobile failure knowledge gained through maintenance experience can be shared across automobile manufacturers and service providers. This would help in design improvements, with ease and efficient undertaking of maintenance activities. This paper proposes the conceptual ontology structure, which is populated with three cases of automobile maintenance. Originality/value This research work is a first attempt to develop an ontological model for automobile failures from their maintenance and service experience. The novelty of the work is in its explicit consideration of all knowledge related to failures and maintenance of automobile systems, with their coding and structuring.

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Investigation of Flow and Forces on a Strongly Accelerated Circular Cylinder

Volume 4: Fluid Structure Interaction ◽

10.1115/pvp2005-71185 ◽

2005 ◽

Author(s):

Vincent Melot ◽

Bruno Auvity ◽

Hassan Peerhossaini

Keyword(s):

Research Work ◽

Numerical Procedure ◽

Operating Conditions ◽

Gravitational Acceleration ◽

Computational Domain ◽

Fluid Medium ◽

Experimental Part ◽

Ale Formulation ◽

Set Up ◽

Under Construction

The present paper exposes the current research work carried out at LABORATOIRE DE THERMOCINE´TIQUE de NANTES within the framework of a collaborative research with DCN PROPULSION concerning the design of nuclear structures subjected to dynamic loading. The case under study consists of a cylinder strongly accelerated from rest in an infinite fluid medium. The main aim of the study is to predict forces acting on the cylinder and to provide a clear description of the flow phenomena. The duration of the mechanical impulse imposed on the cylinder is extremely short (of the order 15 milliseconds). The level of acceleration is 30 times the gravitational acceleration. These operating conditions are representative of a typical shock encountered in the environment of a military ship. This work is composed of a numerical and an experimental part. The numerical modeling is developed in a finite volume formulation. The cylinder is moved inside the computational domain using the ALE formulation for the moving mesh grid. Well-documented experiments on a cylinder impulsively started from rest are simulated to test the numerical procedure and validate our code. Then shocks with sinusoidal acceleration are simulated and compared with the theoretical model of Stokes. The experimental part presents the set-up currently under construction in the laboratory. The cylinder is put in motion by a hydraulic accelerator connected to a power hydraulic station and driven by a computer-controlled servo-valve. The metallic bar holding the cylinder is equipped with strain gauges measuring the integral forces acting on the cylinder.

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On Friction Reduction by Surface Modifications in the TEHL Cam/Tappet-Contact-Experimental and Numerical Studies

Coatings ◽

10.3390/coatings9120843 ◽

2019 ◽

Vol 9 (12) ◽

pp. 843 ◽

Cited By ~ 3

Author(s):

Max Marian ◽

Tim Weikert ◽

Stephan Tremmel

Keyword(s):

Surface Characterization ◽

Surface Engineering ◽

New Technologies ◽

Surface Modifications ◽

Operating Conditions ◽

Friction Reduction ◽

Valve Train ◽

Friction Behavior ◽

Fluid Friction ◽

Wide Range

The overall energy efficiency of machine elements and engine components could be improved by using new technologies such as surface modifications. In the literature, surface engineering approaches like micro-texturing and the application of diamond-like carbon (DLC) coatings were frequently studied separately, with focus on a specific model contact and lubrication conditions. The contribution of the current study is to elucidate and compare the underlying friction reduction mechanisms of the aforementioned surface modifications in an application-orientated manner. The study applied the operating conditions of the thermo-elastohydrodynamically lubricated (TEHL) cam/tappet-contact of the valve train. Therefore, tribological cam/bucket tappet component Stribeck tests were used to determine the friction behavior of ultrashort pulse laser fabricated microtextures and PVD/PECVD deposited silicon-doped amorphous carbon coatings. Moreover, advanced surface characterization methods, as well as numerical TEHL tribo-simulations, were utilized to explore the mechanisms responsible for the observed tribological effects. The results showed that the DLC-coating could reduce the solid and fluid friction force in a wide range of lubrication regimes. Conversely, micro-texturing may reduce solid friction while increasing the fraction of fluid friction.

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Computational Intelligence-Based Optimization Methods for Power Quality and Dynamic Response Enhancement of ac Microgrids

Energies ◽

10.3390/en13164063 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4063 ◽

Cited By ~ 1

Author(s):

Touqeer Ahmed Jumani ◽

Mohd Wazir Mustafa ◽

Nawaf N. Hamadneh ◽

Samer H. Atawneh ◽

Madihah Md. Rasid ◽

...

Keyword(s):

Dynamic Response ◽

Power Quality ◽

Computational Intelligence ◽

Research Work ◽

Optimization Methods ◽

Optimization Techniques ◽

Operating Conditions ◽

Inference System ◽

Study Objective ◽

Comprehensive Review

The penetration of distributed generators (DGs) in the existing power system has brought some real challenges regarding the power quality and dynamic response of the power systems. To overcome the above-mentioned issues, the researchers around the world have tried and tested different control methods among which the computational intelligence (CI) based methods have been found as most effective in mitigating the power quality and transient response problems intuitively. The significance of the mentioned optimization approaches in contemporary ac Microgrid (MG) controls can be observed from the increasing number of published articles and book chapters in the recent past. However, literature related to this important subject is scattered with no comprehensive review that provides detailed insight information on this substantial development. As such, this research work provides a detailed overview of four of the most extensively used CI-based optimization techniques, namely, artificial neural network (ANN), fuzzy logic (FL), adaptive neuro-fuzzy inference system (ANFIS) and genetic algorithm (GA) as applied in ac MG controls from 42 research articles along with their basic working mechanism, merits, and limitations. Due to space and scope constraints, this study excludes the applications of swarm intelligence-based optimization methods in the studied field of research. Each of the mentioned CI algorithms is explored for three major MG control applications i.e., reactive power compensation and power quality, MPPT and MG’s voltage, frequency, and power regulation. In addition, this work provides a classification of the mentioned CI-based optimization studies based on various categories such as key study objective, optimization method applied, DGs utilized, studied MG operating mode, and considered operating conditions in order to ease the searchability and selectivity of the articles for the readers. Hence, it is envisaged that this comprehensive review will provide a valuable one-stop source of knowledge to the researchers working in the field of CI-based ac MG control architectures.

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