Research

21 pages, 2542 KiB

Open AccessArticle

Damping Oriented Design of Thin-Walled Mechanical Components by Means of Multi-Layer Coating Technology

by Giuseppe Catania and Matteo Strozzi

Coatings 2018, 8(2), 73; https://doi.org/10.3390/coatings8020073 - 13 Feb 2018

Cited by 23 | Viewed by 5056

The damping behaviour of multi-layer composite mechanical components, shown by recent research and application papers, is analyzed. A local dissipation mechanism, acting at the interface between any two different layers of the composite component, is taken into account, and a beam model, to [...] Read more.

The damping behaviour of multi-layer composite mechanical components, shown by recent research and application papers, is analyzed. A local dissipation mechanism, acting at the interface between any two different layers of the composite component, is taken into account, and a beam model, to be used for validating the known experimental results, is proposed. Multi-layer prismatic beams, consisting of a metal substrate and of some thin coated layers exhibiting variable stiffness and adherence properties, are considered in order to make it possible to study and validate this assumption. A dynamical model, based on a simple beam geometry but taking into account the previously introduced local dissipation mechanism and distributed visco-elastic constraints, is proposed. Some different application examples of specific multi-layer beams are considered, and some numerical examples concerning the beam free and forced response are described. The influence of the multilayer system parameters on the damping behaviour of the free and forced response of the composite beam is investigated by means of the definition of some damping estimators. Some effective multi-coating configurations, giving a relevant increase of the damping estimators of the coated structure with respect to the same uncoated structure, are obtained from the model simulation, and the results are critically discussed. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

20 pages, 4490 KiB

Open AccessArticle

Experimental Evaluation and Modeling of the Damping Properties of Multi-Layer Coated Composites

by Stefano Amadori, Giuseppe Catania and Angelo Casagrande

Coatings 2018, 8(2), 53; https://doi.org/10.3390/coatings8020053 - 31 Jan 2018

Cited by 8 | Viewed by 4152

Abstract

In this work, the dissipative properties of different coating solutions are compared and a beam mechanical model, taking into account of dissipative actions at the interface between different layers is proposed. The aim is to find optimal coatings to be employed in the [...] Read more.

In this work, the dissipative properties of different coating solutions are compared and a beam mechanical model, taking into account of dissipative actions at the interface between different layers is proposed. The aim is to find optimal coatings to be employed in the production of composites with high damping properties. The investigated coating layers are obtained from different materials and production processes, and are applied on different metallic substrates. The composite specimens, in the form of slender beams, are tested by means of forced excitation dynamic measurements. Force and displacement experimental data, in a wide range of excitation frequencies, are used to estimate the system damping properties. Homogeneous, uncoated specimens are also tested for comparison. A specific identification procedure is used to identify the specimens stress-strain relationship in the frequency domain. The ratio of the imaginary part and the modulus of the specimen estimated complex frequency response function is considered as a measurement of the damping behaviour. A modified third order multi layered beam model, based on the zig-zag beam theory, is proposed. The model takes into account the contribution to the damping behaviour of the frictional actions and slipping at the interface between layers. Frictional actions are modelled by means of a complex, elasto-hysteretic contribution. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

9 pages, 8178 KiB

Open AccessArticle

Influence of Thickness of Multilayered Nano-Structured Coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N on Tool Life of Metal Cutting Tools at Various Cutting Speeds

by Alexey Vereschaka, Elena Kataeva, Nikolay Sitnikov, Anatoliy Aksenenko, Gaik Oganyan and Catherine Sotova

Coatings 2018, 8(1), 44; https://doi.org/10.3390/coatings8010044 - 23 Jan 2018

Cited by 13 | Viewed by 4846

Abstract

This paper considers the influence of thickness of multilayered nano-structured coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N on tool life of metal cutting tools at various cutting speeds (v_c = 250, 300, 350 and 400 m·min⁻¹). The paper investigates the basic mechanical [...] Read more.

This paper considers the influence of thickness of multilayered nano-structured coatings Ti-TiN-(TiCrAl)N and Zr-ZrN-(ZrCrNbAl)N on tool life of metal cutting tools at various cutting speeds (v_c = 250, 300, 350 and 400 m·min⁻¹). The paper investigates the basic mechanical parameters of coatings and the mechanism of coating failure in scratch testing depending on thickness of coating. Cutting tests were conducted in longitudinal turning of steel C45 with tools with the coatings under study of various thicknesses (3, 5, and 7 µm), with an uncoated tool and with a tool with a “reference” coating of TiAlN. The relationship of “cutting speed v_c—tool life T” was built and investigated; and the mechanisms were found to determine the selection of the optimum coating thickness at various cutting speeds. Advantages of cutting tools with these coatings are especially obvious at high cutting speeds (in particular, v_c = 400 m·min⁻¹). If at lower cutting speeds, the longest tool life is shown by tools with thicker coatings (of about 7 μm), then with an increase in cutting speed (especially at v_c = 400 m·min⁻¹) the longest tool life is shown by tools with thinner coating (of about 3 μm). Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

11 pages, 11580 KiB

Open AccessArticle

Effect of Tip Shape of Frictional Stir Burnishing Tool on Processed Layer’s Hardness, Residual Stress and Surface Roughness

by Yoshimasa Takada and Hiroyuki Sasahara

Coatings 2018, 8(1), 32; https://doi.org/10.3390/coatings8010032 - 11 Jan 2018

Cited by 10 | Viewed by 5284

Abstract

Friction stir burnishing (FSB) is a surface-enhancement method used after machining, without the need for an additional device. The FSB process is applied on a machine that uses rotation tools (e.g., machining center or multi-tasking machine). Therefore, the FSB process can be applied [...] Read more.

Friction stir burnishing (FSB) is a surface-enhancement method used after machining, without the need for an additional device. The FSB process is applied on a machine that uses rotation tools (e.g., machining center or multi-tasking machine). Therefore, the FSB process can be applied immediately after the cutting process using the same machine tool. Here, we apply the FSB to the shaft materials of 0.45% C steel using a multi-tasking machine. In the FSB process, the burnishing tool rotates at a high-revolution speed. The thin surface layer is rubbed and stirred as the temperature is increased and decreased. With the FSB process, high hardness or compressive residual stress can be obtained on the surface layer. However, when we applied the FSB process using a 3 mm diameter sphere tip shape tool, the surface roughness increased substantially (R_a = 20 µm). We therefore used four types of tip shape tools to examine the effect of burnishing tool tip radius on surface roughness, hardness, residual stress in the FSB process. Results indicated that the surface roughness was lowest (R_a = 10 µm) when the tip radius tool diameter was large (30 mm). Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

10057 KiB

Open AccessArticle

Effects of Laser Processing Parameters on Texturized Layer Development and Surface Features of Ti6Al4V Alloy Samples

by Juan Manuel Vázquez Martínez, Jorge Salguero Gómez, Moises Batista Ponce and Francisco Javier Botana Pedemonte

Coatings 2018, 8(1), 6; https://doi.org/10.3390/coatings8010006 - 22 Dec 2017

Cited by 16 | Viewed by 4407

Abstract

Surface engineering is widely used in different areas, such as the aerospace industry or the biomechanical and medical fields. Specifically, laser surface modification techniques may obtain specific surface finishes for special applications. In texturing laser procedures, the control of processing parameters has a [...] Read more.

Surface engineering is widely used in different areas, such as the aerospace industry or the biomechanical and medical fields. Specifically, laser surface modification techniques may obtain specific surface finishes for special applications. In texturing laser procedures, the control of processing parameters has a great influence on the geometry and characteristics of the treated area. When these processes are carried out on titanium alloys, thin oxide layers are usually developed on the irradiated surface, formed through the thermochemical combination of vaporized material with atmospheric oxygen in the air. In thermal oxidation treatments of Ti6Al4V, the highest concentration of oxides is mainly composed by rutile (TiO₂), producing surface property modifications such as hardness, among others. In this research, a thermochemical oxidation of Ti6Al4V alloy has been performed through laser texturing, using laser scanning speed (V_s) and pulse rate (f) as process control variables, and its influence on the beam absorption capacity of the modified layer have been analyzed. Combined evaluations of microgeometrical features and mechanical properties, such as hardness, verified that, by means of laser texturing treatments, the ability to generate specific topographies and increase the initial hardness of the alloy is obtained. The most advantageous results for the increase of hardness by thermochemical oxidation have been detected in low scan speeds of laser beam treatments, resulting in an increase of approximately 270% using a scanning speed of 10 mm/s. On the other hand, a dependence between roughness values, in terms of R_a and R_z, and the energy density of pulse (E_d) has been observed, showing higher values of roughness for a 17.68 J/cm² energy density of pulse. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

3103 KiB

Open AccessArticle

Impact Wear of Structural Steel with Yield Strength of 235 MPa in Various Liquids

by Yueting Liu and G.C.A.M. Janssen

Coatings 2017, 7(12), 237; https://doi.org/10.3390/coatings7120237 - 20 Dec 2017

Cited by 1 | Viewed by 3634

Abstract

The wear of pipelines, used in slurry transport, results in high costs for maintenance and replacement. The wear mechanism involves abrasion, corrosion, impact, and the interaction among them. In this work, we study the effect of impact on the wear mechanism and wear [...] Read more.

The wear of pipelines, used in slurry transport, results in high costs for maintenance and replacement. The wear mechanism involves abrasion, corrosion, impact, and the interaction among them. In this work, we study the effect of impact on the wear mechanism and wear rate. Results show that when the effect of impact is small, the wear mechanism is dominated by electrochemically induced surface modification, which leads to a lower wear rate in a corrosive environment than in a non-corrosive environment. By contrast, when the effect of impact is large, the wear mechanism is drastically altered. In that regime plastic deformation is important. The influence of corrosion in the high impact regime can be neglected. Our findings show the importance of including impact effect in the distinction of wear of slurry pipes. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Graphical abstract

8884 KiB

Open AccessArticle

Effect of Coating Palm Oil Clinker Aggregate on the Engineering Properties of Normal Grade Concrete

by Fuad Abutaha, Hashim Abdul Razak and Hussein Adebayo Ibrahim

Coatings 2017, 7(10), 175; https://doi.org/10.3390/coatings7100175 - 21 Oct 2017

Cited by 21 | Viewed by 6918

Abstract

Palm oil clinker (POC) is a waste material generated in large quantities from the palm oil industry. POC, when crushed, possesses the potential to serve as an aggregate for concrete production. Experimental investigation on the engineering properties of concrete incorporating POC as aggregate [...] Read more.

Palm oil clinker (POC) is a waste material generated in large quantities from the palm oil industry. POC, when crushed, possesses the potential to serve as an aggregate for concrete production. Experimental investigation on the engineering properties of concrete incorporating POC as aggregate and filler material was carried out in this study. POC was partially and fully used to replace natural coarse aggregate. The volumetric replacements used were 0%, 20%, 40%, 60%, 80%, and 100%. POC, being highly porous, negatively affected the fresh and hardened concrete properties. Therefore, the particle-packing (PP) method was adopted to measure the surface and inner voids of POC coarse aggregate in the mixtures at different substitution levels. In order to enhance the engineering properties of the POC concrete, palm oil clinker powder (POCP) was used as a filler material to fill up and coat the surface voids of POC coarse, while the rest of the mix constituents were left as the same. Fresh and hardened properties of the POC concrete with and without coating were determined, and the results were compared with the control concrete. The results revealed that coating the surface voids of POC coarse with POCP significantly improved the engineering properties as well as the durability performance of the POC concrete. Furthermore, using POC as an aggregate and filler material may reduce the continuous exploitation of aggregates from primary sources. Also, this approach offers an environmental friendly solution to the ongoing waste problems associated with palm oil waste material. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

13812 KiB

Open AccessArticle

The Phase Evolution and Property of FeCoCrNiAlTi_x High-Entropy Alloying Coatings on Q253 via Laser Cladding

by Bin He, Nannan Zhang, Danyang Lin, Yue Zhang, Fuyu Dong and Deyuan Li

Coatings 2017, 7(10), 157; https://doi.org/10.3390/coatings7100157 - 28 Sep 2017

Cited by 31 | Viewed by 4956

Abstract

High-entropy alloys (HEAs) are emerging as a hot research frontier in the metallic materials field. The study on the effect of alloying elements on the structure and properties of HEAs may contribute to the progress of the research and accelerate the application in [...] Read more.

High-entropy alloys (HEAs) are emerging as a hot research frontier in the metallic materials field. The study on the effect of alloying elements on the structure and properties of HEAs may contribute to the progress of the research and accelerate the application in actual production. FeCoCrNiAlTi_x (x = 0, 0.25, 0.5, 0.75, and 1 in at.%, respectively) HEA coatings with different Ti concentrations were produced on Q235 steel via laser cladding. The constituent phases, microstructure, hardness, and wear resistance of the coatings were investigated by XRD, SEM, microhardness tester and friction-wear tester, respectively. The results show that the structure of the coating is a eutectic microstructure of FCC and BCC₁ at x = 0. The structure of coatings consists of both proeutectic FCC phase and the eutectic structure of BCC₁ and BCC₂. With the continuous addition of Ti, the amount of eutectic structure decreases. The average hardness of the FeCoCrNiAlTi_x HEA coatings at x = 0, 0.25, 0.5, 0.75, and 1 are 432.73 HV, 548.81 HV, 651.03 HV, 769.20 HV, and 966.29 HV, respectively. The hardness of coatings increases with the addition of Ti, where the maximum hardness is achieved for the HEA at x = 1. The wear resistance of the HEA coatings is enhanced with the addition of Ti, and the main worn mechanism is abrasive wear. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

11842 KiB

Open AccessArticle

The Use of Triboemission Imaging and Charge Measurements to Study DLC Coating Failure

by Alessandra Ciniero, Julian Le Rouzic and Tom Reddyhoff

Coatings 2017, 7(8), 129; https://doi.org/10.3390/coatings7080129 - 20 Aug 2017

Cited by 7 | Viewed by 4948

Abstract

We present a study on the simultaneous evolution of the electron emission and surface charge accumulation that occurs during scratching tests in order to monitor coating failure. Steel discs coated with a diamond-like-carbon (DLC) film were scratched in both vacuum (~10⁻⁵ Torr) [...] Read more.

We present a study on the simultaneous evolution of the electron emission and surface charge accumulation that occurs during scratching tests in order to monitor coating failure. Steel discs coated with a diamond-like-carbon (DLC) film were scratched in both vacuum (~10⁻⁵ Torr) and atmospheric conditions, with electron emission and surface charge being measured by a system of microchannel plates and an electrometer, respectively. The results highlight a positive correlation between emission intensity values, surface charge measurements and surface damage topography, suggesting the effective use of these techniques to monitor coating wear in real time. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Graphical abstract

3347 KiB

Open AccessArticle

Thermal-Sprayed Coatings on Bushing and Sleeve-Pipe Surfaces in Continuous Galvanizing Sinking Roller Production Line Applications

by Guangwei Zhang, Deyuan Li, Ning Zhang, Nannan Zhang and Sihua Duan

Coatings 2017, 7(8), 113; https://doi.org/10.3390/coatings7080113 - 02 Aug 2017

Cited by 6 | Viewed by 5014

Abstract

This paper describes thermal spray techniques for making hard coatings on bushing and sleeve component surfaces. Specifically, plasma-arc welding was used to produce 5-mm thick Co-Cr alloy welding overlays on the bushing, while a high-velocity oxy-fuel spraying technique and laser re-melting technique were [...] Read more.

This paper describes thermal spray techniques for making hard coatings on bushing and sleeve component surfaces. Specifically, plasma-arc welding was used to produce 5-mm thick Co-Cr alloy welding overlays on the bushing, while a high-velocity oxy-fuel spraying technique and laser re-melting technique were used to produce thinner coatings of Co-Cr-Ni+WC of about 1mm thickness on the sleeve-pipe counterparts. The surface-treated components were then submerged in liquid zinc to study the corrosive behaviour of the surface coating and substrate. Both the scanning electron microscope and energy dispersive spectrometer analyses were used to study the microstructure and phase composition of both coatings and substrates prior to and after corrosion experiments. The results show that the microstructure of the bushing consists of γ-cobalt solid solution as well as the eutectic structure of γ-cobalt and carbides, which have good corrosive resistance against molten zinc. Meanwhile, the microstructure of the sleeve pipe consists of a Co-Cr solid solution with various forms of carbides, which displays the combined properties of toughness with good corrosive resistance to molten zinc. Full article

(This article belongs to the Special Issue Manufacturing and Surface Engineering)

► Show Figures

Figure 1

Journal Menu

Journal Browser

Manufacturing and Surface Engineering

Share This Special Issue

Special Issue Editor

Special Issue Information

Published Papers (10 papers)

Research

Further Information

Guidelines

MDPI Initiatives

Follow MDPI