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Informacje o czasopiśmie
Format
Czasopismo
eISSN
2300-5319
Pierwsze wydanie
22 Jan 2014
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

Tom 10 (2016): Zeszyt 2 (June 2016)

Informacje o czasopiśmie
Format
Czasopismo
eISSN
2300-5319
Pierwsze wydanie
22 Jan 2014
Częstotliwość wydawania
4 razy w roku
Języki
Angielski

Wyszukiwanie

12 Artykułów
access type Otwarty dostęp

Influence of Tempering on Mechanical Properties of Induction Bents below 540°C

Data publikacji: 08 Jun 2016
Zakres stron: 81 - 86

Abstrakt

Abstract

The article describes basic principles of induction bending and the change of mechanical properties from as received (straight) pipe made from HSLA steel to induction bend. The main purpose of this article is to experiment with tempering temperatures below 540°C. After tempering at 540°C which is the lowest recommended temperature for post bend heat treatment (PBHT) according to CSA specifications (Canadian Standards Association) the induction bend area in many cases does not achieve the minimum required mechanical properties and therefore it is not accepted for usage. In this article mechanical properties such as tensile, toughness, hardness are evaluated. Also the article contains microstructural analyses and comparison of bended and heat treated samples.

Słowa kluczowe

  • HSLA
  • Induction
  • Bending
  • Tempering
access type Otwarty dostęp

Type Synthesis, Modelling and Analysis of the Manipulator for Wheel-Legged Robot

Data publikacji: 08 Jun 2016
Zakres stron: 87 - 91

Abstrakt

Abstract

The aim of this article is to present the concept of wheel-legged mobile manipulator, which is a combination of mobile platform with specially selected suspension system and a manipulator. First, a literature review was performed and own solution proposed. The kinematic structure of manipulator, selected simulation results, physical model and the concept of the control system has been presented. Geometry synthesis was used to design basic dimension. Structural synthesis was performed according to the intermediate chain method. Simulations were performed using the multibody dynamics simulation software. New approach in the field of the mobile manipulators was presented as a result.

Słowa kluczowe

  • Mobile Manipulator
  • Multibody Dynamics Analysis
  • Wheel-Legged Platform
access type Otwarty dostęp

Multi-UAV Flight using Virtual Structure Combined with Behavioral Approach

Data publikacji: 08 Jun 2016
Zakres stron: 92 - 99

Abstrakt

Abstract

Implementations of multi-UAV systems can be divided mainly into two different approaches, centralised system that synchronises positions of each vehicle by a ground station and an autonomous system based on decentralised control, which offers more flexibility and independence. Decentralisation of multi-UAV control entails the need for information sharing between all vehicles, what in some cases could be problematic due to a significant amount of data to be sent over the wireless network. To improve the reliability and the throughput of information sharing inside the formation of UAVs, this paper proposes an approach that combines virtual structure with a leader and two flocking behaviours. Each UAV has assigned different virtual migration point referenced to the leader's position which is simultaneously the origin of a formation reference frame. All migration points create together a virtual rigid structure. Each vehicle uses local behaviours of cohesion and repulsion respectively, to track its own assigned point in the structure and to avoid a collision with the previous UAV in the structure. To calculate parameters of local behaviours, each UAV should know position and attitude of the leader to define the formation reference frame and also the actual position of the previous UAV in the structure. Hence, information sharing can be based on a chain of local peer-to-peer communication between two consecutive vehicles in the structure. In such solution, the information about the leader could be sequentially transmitted from one UAV to another. Numerical simulations were prepared and carried out to verify the effectiveness of the presented approach. Trajectories recorded during those simulations show collective, coherence and collision-free flights of the formation created with five UAVs.

Słowa kluczowe

  • Multi-UAV
  • Virtual Structure
  • Formation
  • Flocking Behaviors
access type Otwarty dostęp

The Use of Spectral Method for Fatigue Life Assessment for Non-Gaussian Random Loads

Data publikacji: 08 Jun 2016
Zakres stron: 100 - 103

Abstrakt

Abstract

The well-known problem with the fatigue lifetime assessment of non-Gaussian loading signals with the use of spectral method has been presented in the paper. A correction factors that transform the non-Gaussian signal into an equivalent Gaussian signal proposed by Bracessi et al. (2009) has been used for the purpose of lifetime calculations together with Palmgren-Miner Hypothesis. The calculations have been performed for the 10HNAP steel under random non-Gaussian load with four dominating frequencies. The signal has been generated on the test stand SHM250 for random tension-compression tests. The results with zero and non-zero mean stresses have been used to calculate the fatigue life with the frequency domain method based on Dirlik’s model and with a time domain method with the use of the rainflow cycle counting algorithm. The obtained calculation results have been compared with experimental results.

Słowa kluczowe

  • Spectral Method
  • Fatigue Life
  • Random Loading
  • Non-Gaussian
access type Otwarty dostęp

Influence of Corrugation Depth on Lateral Stability of Cold-Formed Steel Beams of Corrugated Webs

Data publikacji: 08 Jun 2016
Zakres stron: 104 - 111

Abstrakt

Abstract

The beams of thin corrugated web afford a significant weight reduction compared with hot-rolled or welded ones. In the initial solutions, the flanges are made of flat plates, welded to the sinusoidal web sheet, requiring a specific welding technology. A new solution is proposed by the authors, in which the beam is composed by a web of trapezoidal cold-formed steel sheet and flanges of back-to-back lipped channel sections. For connecting flanges to the web self-drilling screws are used. The paper summarizes the experimental and numerical investigations carried out at the CEMSIG Research Centre (www.ct.upt.ro/centre/cemsig/) of the Politehnica University of Timisoara and, at the end, presents the influence of corrugation depth of web on the lateral stability of the beams.

Słowa kluczowe

  • Corrugated Web Beam
  • Cold-Formed Steel Solution
  • Discrete Fasteners
  • Self-Drilling Screws
  • Experimental Investigation
access type Otwarty dostęp

The Parameter Correlation of Acoustic Emission and High-Frequency Vibrations in the Assessment Process of the Operating State of the Technical System

Data publikacji: 08 Jun 2016
Zakres stron: 112 - 116

Abstrakt

Abstract

The article describes application of selected methods of technical diagnostics for assessing the operating status of precision gearboxes. Within the confines of experimental measurements in the field of physical metallurgy materials of diagnosed system were being examined while taking into account the process of degradation of material properties during operation of monitored gearboxes. Measurements and collecting of dynamic data were realized on 4 selected gearboxes where a high-frequency vibrations and acoustic emission (noise) measurements were carried out. Retrieved values were subsequently used for mutual correlation and verification of applied methods. Results of both selected methods underlined unsatisfactory operation status with 3 inspected gearboxes. Measured values were identified as being above suggested caution limit of Alarm 2, representing a level of danger.

Słowa kluczowe

  • Technical Diagnostics
  • Vibrodiagnostics
  • Analysis of Dynamic Signal
access type Otwarty dostęp

Accuracy of Spindle Units with Hydrostatic Bearings

Data publikacji: 08 Jun 2016
Zakres stron: 117 - 124

Abstrakt

Abstract

The work is devoted to the research of precision regularities in a spindle unit by the trajectory of the spindle installed on hydrostatic bearings. The mathematical model of trajectories spindle with lumped parameters that allows to define the position of the spindle with regard the simultaneous influence of design parameters, geometrical deviations ofform, temperature deformation bearing surfaces, the random nature of operational parameters and technical loads of hydrostatic bearings has been developed. Based on the results of numerical modeling the influence of shape errors of bearing surface of hydrostatic bearing on the statistical characteristics of the radius vector trajectories of the spindle by varying the values rotational speed of the spindle and oil pressure in front hydrostatic bearing has been developed. The obtained statistical regularities of precision spindle unit have been confirmed experimentally. It has been shown that an effective way to increase the precision of spindle units is to regulate the size of the gap in hydrostatic spindle bearings. The new design of an adjustable hydrostatic bearing, which can improve the accuracy of regulation size gap has been proposed.

Słowa kluczowe

  • Spindle
  • Hydrostatic Bearing
  • Spindle Unit
  • Adjustable Hydrostatic Bearing
  • Machining Accuracy
  • Trajectory
  • Bearing Surface Imperfection
access type Otwarty dostęp

Constitutive Modelling of Damage Evolution and Martensitic Transformation in 316L Stainless Steel

Data publikacji: 08 Jun 2016
Zakres stron: 125 - 132

Abstrakt

Abstract

In this work, the constitutive model, derived with the use of thermodynamic of irreversible processes framework is presented. The model is derived under the assumption of small strains. Plastic strain induced martensitic phase transformation is considered in the austenitic matrix where the volume fraction of the martensite is reflected by a scalar parameter. The austenitic matrix is assumed as the elastic-plastic material and martensitic phase is assumed as randomly distributed and randomly oriented inclusions. Both phases are affected by damage evolution but there is no distinction in the model between damage in austenite and martensite.

Słowa kluczowe

  • Constitutive Modelling
  • Dissipative Materials
  • Phase Transformation
  • Damage Evolution
access type Otwarty dostęp

Transient Vibrations of an Elastic Cylinder Inserted in the Elastic Medium

Data publikacji: 08 Jun 2016
Zakres stron: 133 - 136

Abstrakt

Abstract

Using method of Laguerre polynomials we have obtained the solution of the dynamic problem of the theory of elasticity for elastic cylinder inserted into massive body modeled as a space. The source of non-stationary processes in composite is high intensity force load of the inner surface of the cylinder. On the surface separation of materials of space and cylinder the conditions of ideal mechanical contact are satisfied. The solution is obtained as series of Laguerre polynomials, which coefficients are found from recurrent relations. The results of numerical analysis of transient stress-strain state in elastic space with cylindrical insertion might be used for the technological process of hydraulic fracturing during shale gas extraction.

Słowa kluczowe

  • Transient Wave Propagation
  • Nongomogeneous Medium
  • Analytical Solution
  • Laguerre Polynomials
access type Otwarty dostęp

Modelling the Meshing of Cycloidal Gears

Data publikacji: 08 Jun 2016
Zakres stron: 137 - 140

Abstrakt

Abstract

Cycloidal drives belong to the group of planetary gear drives. The article presents the process of modelling a cycloidal gear. The full profile of the planetary gear is determined from the following parameters: ratio of the drive, eccentricity value, the equidistant (ring gear roller radius), epicycloid reduction ratio, roller placement diameter in the ring gear. Joong-Ho Shin’s and Soon-Man Kwon’s article (Shin and Know, 2006) was used to determine the profile outline of the cycloidal planetary gear lobes. The result was a scatter chart with smooth lines and markers, presenting the full outline of the cycloidal gear.

Słowa kluczowe

  • Cycloidal Drive
  • Modelling
  • Profile
  • Planetary Gear
  • Gear
access type Otwarty dostęp

Coupled Static and Dynamic Buckling Modelling of Thin-Walled Structures in Elastic Range Review of Selected Problems

Data publikacji: 08 Jun 2016
Zakres stron: 141 - 149

Abstrakt

Abstract

A review of papers that investigate the static and dynamic coupled buckling and post-buckling behaviour of thin-walled structures is carried out. The problem of static coupled buckling is sufficiently well-recognized. The analysis of dynamic interactive buckling is limited in practice to columns, single plates and shells. The applications of finite element method (FEM) or/and analytical-numerical method (ANM) to solve interaction buckling problems are on-going. In Poland, the team of scientists from the Department of Strength of Materials, Lodz University of Technology and co-workers developed the analytical-numerical method. This method allows to determine static buckling stresses, natural frequencies, coefficients of the equation describing the post-buckling equilibrium path and dynamic response of the plate structure subjected to compression load and/or bending moment. Using the dynamic buckling criteria, it is possible to determine the dynamic critical load. They presented a lot of interesting results for problems of the static and dynamic coupled buckling of thin-walled plate structures with complex shapes of cross-sections, including an interaction of component plates. The most important advantage of presented analytical-numerical method is that it enables to describe all buckling modes and the post-buckling behaviours of thin-walled columns made of different materials. Thin isotropic, orthotropic or laminate structures were considered.

Słowa kluczowe

  • Interaction
  • Buckling
  • Thin-Walled Structures
  • FEM
  • Analytical-Numerical Method
  • Review
access type Otwarty dostęp

Direct Current and Pulsed Direct Current Plasma Nitriding of Ferrous Materials a Critical Review

Data publikacji: 08 Jun 2016
Zakres stron: 150 - 158

Abstrakt

Abstract

Nowadays, the improvement of ferrous materials performance is a problem of high interest. One of well-known wear- and corrosion properties improving technique is plasma nitriding, in which elemental nitrogen is introduced to the surface of a metal part for subsequent diffusion into the material. As a result, a compound, “white” layer and a diffusion zone are formed at the detail’s surface. Most of the authors positively describe the effects of surface ion nitiding. On the other hand, there are also reports on adverse effects of direct current and pulsed direct current plasma nitriding on ferrous materials performance. Therefore, an attempt to provide comprehensive summary on direct current and pulsed direct current ion nitriding and its influence on ferrous materials’ mechanical and corrosion properties has been made. According to the results, some of the technique drawbacks are hard to avoid in mass production.

Słowa kluczowe

  • Plasma Nitriding
  • Ion Nitriding
  • Direct Current Plasma Nitriding
  • Pulsed Direct Current Plasma Nitriding
  • Edge Effect
12 Artykułów
access type Otwarty dostęp

Influence of Tempering on Mechanical Properties of Induction Bents below 540°C

Data publikacji: 08 Jun 2016
Zakres stron: 81 - 86

Abstrakt

Abstract

The article describes basic principles of induction bending and the change of mechanical properties from as received (straight) pipe made from HSLA steel to induction bend. The main purpose of this article is to experiment with tempering temperatures below 540°C. After tempering at 540°C which is the lowest recommended temperature for post bend heat treatment (PBHT) according to CSA specifications (Canadian Standards Association) the induction bend area in many cases does not achieve the minimum required mechanical properties and therefore it is not accepted for usage. In this article mechanical properties such as tensile, toughness, hardness are evaluated. Also the article contains microstructural analyses and comparison of bended and heat treated samples.

Słowa kluczowe

  • HSLA
  • Induction
  • Bending
  • Tempering
access type Otwarty dostęp

Type Synthesis, Modelling and Analysis of the Manipulator for Wheel-Legged Robot

Data publikacji: 08 Jun 2016
Zakres stron: 87 - 91

Abstrakt

Abstract

The aim of this article is to present the concept of wheel-legged mobile manipulator, which is a combination of mobile platform with specially selected suspension system and a manipulator. First, a literature review was performed and own solution proposed. The kinematic structure of manipulator, selected simulation results, physical model and the concept of the control system has been presented. Geometry synthesis was used to design basic dimension. Structural synthesis was performed according to the intermediate chain method. Simulations were performed using the multibody dynamics simulation software. New approach in the field of the mobile manipulators was presented as a result.

Słowa kluczowe

  • Mobile Manipulator
  • Multibody Dynamics Analysis
  • Wheel-Legged Platform
access type Otwarty dostęp

Multi-UAV Flight using Virtual Structure Combined with Behavioral Approach

Data publikacji: 08 Jun 2016
Zakres stron: 92 - 99

Abstrakt

Abstract

Implementations of multi-UAV systems can be divided mainly into two different approaches, centralised system that synchronises positions of each vehicle by a ground station and an autonomous system based on decentralised control, which offers more flexibility and independence. Decentralisation of multi-UAV control entails the need for information sharing between all vehicles, what in some cases could be problematic due to a significant amount of data to be sent over the wireless network. To improve the reliability and the throughput of information sharing inside the formation of UAVs, this paper proposes an approach that combines virtual structure with a leader and two flocking behaviours. Each UAV has assigned different virtual migration point referenced to the leader's position which is simultaneously the origin of a formation reference frame. All migration points create together a virtual rigid structure. Each vehicle uses local behaviours of cohesion and repulsion respectively, to track its own assigned point in the structure and to avoid a collision with the previous UAV in the structure. To calculate parameters of local behaviours, each UAV should know position and attitude of the leader to define the formation reference frame and also the actual position of the previous UAV in the structure. Hence, information sharing can be based on a chain of local peer-to-peer communication between two consecutive vehicles in the structure. In such solution, the information about the leader could be sequentially transmitted from one UAV to another. Numerical simulations were prepared and carried out to verify the effectiveness of the presented approach. Trajectories recorded during those simulations show collective, coherence and collision-free flights of the formation created with five UAVs.

Słowa kluczowe

  • Multi-UAV
  • Virtual Structure
  • Formation
  • Flocking Behaviors
access type Otwarty dostęp

The Use of Spectral Method for Fatigue Life Assessment for Non-Gaussian Random Loads

Data publikacji: 08 Jun 2016
Zakres stron: 100 - 103

Abstrakt

Abstract

The well-known problem with the fatigue lifetime assessment of non-Gaussian loading signals with the use of spectral method has been presented in the paper. A correction factors that transform the non-Gaussian signal into an equivalent Gaussian signal proposed by Bracessi et al. (2009) has been used for the purpose of lifetime calculations together with Palmgren-Miner Hypothesis. The calculations have been performed for the 10HNAP steel under random non-Gaussian load with four dominating frequencies. The signal has been generated on the test stand SHM250 for random tension-compression tests. The results with zero and non-zero mean stresses have been used to calculate the fatigue life with the frequency domain method based on Dirlik’s model and with a time domain method with the use of the rainflow cycle counting algorithm. The obtained calculation results have been compared with experimental results.

Słowa kluczowe

  • Spectral Method
  • Fatigue Life
  • Random Loading
  • Non-Gaussian
access type Otwarty dostęp

Influence of Corrugation Depth on Lateral Stability of Cold-Formed Steel Beams of Corrugated Webs

Data publikacji: 08 Jun 2016
Zakres stron: 104 - 111

Abstrakt

Abstract

The beams of thin corrugated web afford a significant weight reduction compared with hot-rolled or welded ones. In the initial solutions, the flanges are made of flat plates, welded to the sinusoidal web sheet, requiring a specific welding technology. A new solution is proposed by the authors, in which the beam is composed by a web of trapezoidal cold-formed steel sheet and flanges of back-to-back lipped channel sections. For connecting flanges to the web self-drilling screws are used. The paper summarizes the experimental and numerical investigations carried out at the CEMSIG Research Centre (www.ct.upt.ro/centre/cemsig/) of the Politehnica University of Timisoara and, at the end, presents the influence of corrugation depth of web on the lateral stability of the beams.

Słowa kluczowe

  • Corrugated Web Beam
  • Cold-Formed Steel Solution
  • Discrete Fasteners
  • Self-Drilling Screws
  • Experimental Investigation
access type Otwarty dostęp

The Parameter Correlation of Acoustic Emission and High-Frequency Vibrations in the Assessment Process of the Operating State of the Technical System

Data publikacji: 08 Jun 2016
Zakres stron: 112 - 116

Abstrakt

Abstract

The article describes application of selected methods of technical diagnostics for assessing the operating status of precision gearboxes. Within the confines of experimental measurements in the field of physical metallurgy materials of diagnosed system were being examined while taking into account the process of degradation of material properties during operation of monitored gearboxes. Measurements and collecting of dynamic data were realized on 4 selected gearboxes where a high-frequency vibrations and acoustic emission (noise) measurements were carried out. Retrieved values were subsequently used for mutual correlation and verification of applied methods. Results of both selected methods underlined unsatisfactory operation status with 3 inspected gearboxes. Measured values were identified as being above suggested caution limit of Alarm 2, representing a level of danger.

Słowa kluczowe

  • Technical Diagnostics
  • Vibrodiagnostics
  • Analysis of Dynamic Signal
access type Otwarty dostęp

Accuracy of Spindle Units with Hydrostatic Bearings

Data publikacji: 08 Jun 2016
Zakres stron: 117 - 124

Abstrakt

Abstract

The work is devoted to the research of precision regularities in a spindle unit by the trajectory of the spindle installed on hydrostatic bearings. The mathematical model of trajectories spindle with lumped parameters that allows to define the position of the spindle with regard the simultaneous influence of design parameters, geometrical deviations ofform, temperature deformation bearing surfaces, the random nature of operational parameters and technical loads of hydrostatic bearings has been developed. Based on the results of numerical modeling the influence of shape errors of bearing surface of hydrostatic bearing on the statistical characteristics of the radius vector trajectories of the spindle by varying the values rotational speed of the spindle and oil pressure in front hydrostatic bearing has been developed. The obtained statistical regularities of precision spindle unit have been confirmed experimentally. It has been shown that an effective way to increase the precision of spindle units is to regulate the size of the gap in hydrostatic spindle bearings. The new design of an adjustable hydrostatic bearing, which can improve the accuracy of regulation size gap has been proposed.

Słowa kluczowe

  • Spindle
  • Hydrostatic Bearing
  • Spindle Unit
  • Adjustable Hydrostatic Bearing
  • Machining Accuracy
  • Trajectory
  • Bearing Surface Imperfection
access type Otwarty dostęp

Constitutive Modelling of Damage Evolution and Martensitic Transformation in 316L Stainless Steel

Data publikacji: 08 Jun 2016
Zakres stron: 125 - 132

Abstrakt

Abstract

In this work, the constitutive model, derived with the use of thermodynamic of irreversible processes framework is presented. The model is derived under the assumption of small strains. Plastic strain induced martensitic phase transformation is considered in the austenitic matrix where the volume fraction of the martensite is reflected by a scalar parameter. The austenitic matrix is assumed as the elastic-plastic material and martensitic phase is assumed as randomly distributed and randomly oriented inclusions. Both phases are affected by damage evolution but there is no distinction in the model between damage in austenite and martensite.

Słowa kluczowe

  • Constitutive Modelling
  • Dissipative Materials
  • Phase Transformation
  • Damage Evolution
access type Otwarty dostęp

Transient Vibrations of an Elastic Cylinder Inserted in the Elastic Medium

Data publikacji: 08 Jun 2016
Zakres stron: 133 - 136

Abstrakt

Abstract

Using method of Laguerre polynomials we have obtained the solution of the dynamic problem of the theory of elasticity for elastic cylinder inserted into massive body modeled as a space. The source of non-stationary processes in composite is high intensity force load of the inner surface of the cylinder. On the surface separation of materials of space and cylinder the conditions of ideal mechanical contact are satisfied. The solution is obtained as series of Laguerre polynomials, which coefficients are found from recurrent relations. The results of numerical analysis of transient stress-strain state in elastic space with cylindrical insertion might be used for the technological process of hydraulic fracturing during shale gas extraction.

Słowa kluczowe

  • Transient Wave Propagation
  • Nongomogeneous Medium
  • Analytical Solution
  • Laguerre Polynomials
access type Otwarty dostęp

Modelling the Meshing of Cycloidal Gears

Data publikacji: 08 Jun 2016
Zakres stron: 137 - 140

Abstrakt

Abstract

Cycloidal drives belong to the group of planetary gear drives. The article presents the process of modelling a cycloidal gear. The full profile of the planetary gear is determined from the following parameters: ratio of the drive, eccentricity value, the equidistant (ring gear roller radius), epicycloid reduction ratio, roller placement diameter in the ring gear. Joong-Ho Shin’s and Soon-Man Kwon’s article (Shin and Know, 2006) was used to determine the profile outline of the cycloidal planetary gear lobes. The result was a scatter chart with smooth lines and markers, presenting the full outline of the cycloidal gear.

Słowa kluczowe

  • Cycloidal Drive
  • Modelling
  • Profile
  • Planetary Gear
  • Gear
access type Otwarty dostęp

Coupled Static and Dynamic Buckling Modelling of Thin-Walled Structures in Elastic Range Review of Selected Problems

Data publikacji: 08 Jun 2016
Zakres stron: 141 - 149

Abstrakt

Abstract

A review of papers that investigate the static and dynamic coupled buckling and post-buckling behaviour of thin-walled structures is carried out. The problem of static coupled buckling is sufficiently well-recognized. The analysis of dynamic interactive buckling is limited in practice to columns, single plates and shells. The applications of finite element method (FEM) or/and analytical-numerical method (ANM) to solve interaction buckling problems are on-going. In Poland, the team of scientists from the Department of Strength of Materials, Lodz University of Technology and co-workers developed the analytical-numerical method. This method allows to determine static buckling stresses, natural frequencies, coefficients of the equation describing the post-buckling equilibrium path and dynamic response of the plate structure subjected to compression load and/or bending moment. Using the dynamic buckling criteria, it is possible to determine the dynamic critical load. They presented a lot of interesting results for problems of the static and dynamic coupled buckling of thin-walled plate structures with complex shapes of cross-sections, including an interaction of component plates. The most important advantage of presented analytical-numerical method is that it enables to describe all buckling modes and the post-buckling behaviours of thin-walled columns made of different materials. Thin isotropic, orthotropic or laminate structures were considered.

Słowa kluczowe

  • Interaction
  • Buckling
  • Thin-Walled Structures
  • FEM
  • Analytical-Numerical Method
  • Review
access type Otwarty dostęp

Direct Current and Pulsed Direct Current Plasma Nitriding of Ferrous Materials a Critical Review

Data publikacji: 08 Jun 2016
Zakres stron: 150 - 158

Abstrakt

Abstract

Nowadays, the improvement of ferrous materials performance is a problem of high interest. One of well-known wear- and corrosion properties improving technique is plasma nitriding, in which elemental nitrogen is introduced to the surface of a metal part for subsequent diffusion into the material. As a result, a compound, “white” layer and a diffusion zone are formed at the detail’s surface. Most of the authors positively describe the effects of surface ion nitiding. On the other hand, there are also reports on adverse effects of direct current and pulsed direct current plasma nitriding on ferrous materials performance. Therefore, an attempt to provide comprehensive summary on direct current and pulsed direct current ion nitriding and its influence on ferrous materials’ mechanical and corrosion properties has been made. According to the results, some of the technique drawbacks are hard to avoid in mass production.

Słowa kluczowe

  • Plasma Nitriding
  • Ion Nitriding
  • Direct Current Plasma Nitriding
  • Pulsed Direct Current Plasma Nitriding
  • Edge Effect

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