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RESIDUAL stresses, STRESS-strain curves, and QUALITY control

Residual stress has a great influence on the metal, but it is difficult to measure at small area using a general method. Residual stress calculations using the Vickers indentation can solve this problem. In this paper, a numerical simulation has been made for the residual stress measurement method of metal material deformed by high-speed impact. Then, the stress-strain curve at the highspeed deformation was confirmed through actual experiments, and the residual stresses generated thereafter were calculated by the Vickers indenter method. A Vickers indentation analysis under the same conditions was performed at the position where a residual stress of about 169.39 MPa was generated. Experiments were carried out and high speed impact was applied to the specimen to generate residual stress. The obtained results indicate that it is possible to identify residual stresses in various metals with various shapes through Vickers indentation measurements, and to use them for process and quality control. [ABSTRACT FROM AUTHOR]

HYDROPHOBIC interactions, POWDER injection molding, SURFACE preparation, FORCEPS, and THERMOGRAVIMETRY

Hydrophobic surgical forceps of end-effectors for laparoscopic operations or minimally invasive surgery were developed through powder injection molding (PIM) and surface treatment. Processing conditions for mixing, debinding, and sintering were investigated to produce defect-free components. An optimum solid loading was determined by torque rheometry experiments. The optimized processing conditions for debinding and sintering were designed through the measurement of weight loss and shrinkage behavior by thermogravimetric analysis and dilatometry experiments. After producing the surgical forceps based on the optimized processing conditions via PIM, surface treatment was carried out to generate the hydrophobic structure on the surface. [ABSTRACT FROM AUTHOR]

ANODES, COPPER, ELECTRIC properties, ELECTROPLATING, TITANIUM, ELECTROCHEMICAL analysis, and METALLIC oxides

In order to enhance the long-term stability of DSA for copper electroplating process, in the present study, noble metal oxides with excellent electrochemical properties was used and optimum condition was determined the ratio of noble metal oxides, surface pre-treatment of titanium substrate and heat treatment. The effect of the surface pretreatment of titanium substrate and ratio of noble metal oxides were estimated by accelerated test at the highly current density conditions. The lifetime of DSA increase six-fold higher as the oxide thickness of Ta 7 : Ir 3 composition ratio. Under the optimal condition, surface pretreatment led to dramatic increase in the lifetime of DSA. [ABSTRACT FROM AUTHOR]

Dimensionally Stable Anode, Surface treatment, Life time, Copper, Electrodeposition, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

In order to enhance the long-term stability of DSA for copper electroplating process, in the present study, noble metal oxides with excellent electrochemical properties was used and optimum condition was determined the ratio of noble metal oxides, surface pre-treatment of titanium substrate and heat treatment. The effect of the surface pretreatment of titanium substrate and ratio of noble metal oxides were estimated by accelerated test at the highly current density conditions. The lifetime of DSA increase six-fold higher as the oxide thickness of Ta 7 : Ir 3 composition ratio. Under the optimal condition, surface pretreatment led to dramatic increase in the lifetime of DSA.

ALUMINUM metallography, ANODIC oxidation of metals, SURFACE properties, METALLIC composites, CORROSION resistance, and HEAT treatment

An huge interest is observed in last years in metal matrix composite, mostly light metal based, which have found their applications in many industry branches, among others in the aircraft industry, automotive-, and armaments ones, as well as in electrical engineering and electronics, where one of the most important issue is related to the corrosion resistance, especially on the surface layer of the used aluminium alloys. This elaboration presents the influence of ceramic phase on the corrosion resistance, quality of the surface layer its thickness and structure of an anodic layer formed on aluminium alloys. As test materials it was applied the aluminium alloys Al-Si-Cu and Al-Cu-Mg, for which heat treatment processes and corrosion tests were carried out. It was presented herein grindability test results and metallographic examination, as well. Hardness of the treated alloys with those ones subjected to corrosion process were compared. [ABSTRACT FROM AUTHOR]

SURFACE preparation, ALUMINUM alloys, LASER ablation, SEMICONDUCTOR lasers, TRIBOLOGY, and TUNGSTEN carbide

In this work, the influence of a high power diode laser surface treatment on the structure and properties of aluminium alloy has been determined. The aim of this study was to improve the mechanical and tribological properties of the surface layer of the aluminium alloy by simultaneously melting and feeding tungsten carbide particles into the molten pool. During the process was used high-power diode laser HPDL. In order to remelt the aluminium alloy surface the HPDL laser of 1.8, 2.0 and 2.2 kW laser beam power has been used. The linear laser scan rate of the beam was set 0.5 cm/s. In order to protect the liquid metal during laser treatment was used argon. As a base material was used aluminium alloy ENAC -AlMg9. To improve the surface mechanical and wear properties of the applied aluminium alloy was used biphasic tungsten carbide WC/W2C. The size of alloying powder was in the range 110-210 µm. The ceramic powder was introduced in the remelting zone by a gravity feeder at a constant rate of 8 g/m. [ABSTRACT FROM AUTHOR]

ALUMINUM alloys, CASTING (Manufacturing process), ANODIC oxidation of metals, STRUCTURAL analysis (Engineering), and METALLOGRAPHY

This paper presents the influence of casting method and anodic treatment parameters on thickness and structure of an anodic layer formed on aluminium alloys. As test materials was used the aluminium alloy AlSi9Cu3, which was adopted to the casting process and anodic treatment. In this paper are presented the wear test results and metallographic examination, as well as hardness of non-anodised and anodised alloys subjected to anodising process. The investigations were performed using light and electron microscopy (AFM) for the microstructure determination. The morphology and size of the layer was also possible to determine. The anodising conditions for surface hardening and its influence on properties was analysed. The structure of the surface laser tray changes in a way, that there is a different thickness of the produced layer. The aluminium samples were examined in terms of metallography using the optical microscope with different image techniques as well as light microscope. Improving the anodization technology with appliance of different anodising conditions. Some other investigation should be performed in the future, but the knowledge found in this research concerning the proper process parameters for each type of alloy shows an interesting investigation direction. The combination of metallographic investigation for cast aluminium alloys - including electron microscope investigation - and anodising parameters makes the investigation very attractive for automobile industry, aviation industry, and others, where aluminium alloys plays an important role. [ABSTRACT FROM AUTHOR]

TOOL-steel, COMPOSITE coating, LASER peening, SURFACE chemistry, CRYSTAL structure, and MECHANICAL wear

Investigations include alloying the PMHSS6-5-3 steel surface layer with carbide and ceramic powders WC, VC, TiC, SiC, Si3N4 and Al2O3, using the high power diode laser (HPDL). Laser treatment is especially promising for solving contemporary surface engineering problems making it possible to focus precisely the delivered energy in the form of heat in the surface layer. The structural mechanism was determined of surface layers development, effect was studied of alloying parameters, method on structure refinement and influence of these factors on the mechanical properties of surface layer, and especially on its abrasive wear resistance. The fine grained martensite structure is responsible for hardness increase of the alloyed layer. The tribological wear relationships were determined for laser treated surface layers, determining friction coefficient, and wear trace shape developed due to the abrasive wear of the investigated surfaces. Comparison of the laser treatment parameters and tribological properties of surface layer after remelting and alloying with hard particles of the PMHSS6-5-3 steel using the high power diode laser to obtain the optimum service properties is the outcome of the investigations carried out. [ABSTRACT FROM AUTHOR]

Surface Treatment, Aluminium alloys, Ceramic materials, Composites, Corrosion resistance, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

An huge interest is observed in last years in metal matrix composite, mostly light metal based, which have found their applications in many industry branches, among others in the aircraft industry, automotive-, and armaments ones, as well as in electrical engineering and electronics, where one of the most important issue is related to the corrosion resistance, especially on the surface layer of the used aluminium alloys. This elaboration presents the influence of ceramic phase on the corrosion resistance, quality of the surface layer its thickness and structure of an anodic layer formed on aluminium alloys. As test materials it was applied the aluminium alloys Al-Si-Cu and Al-Cu-Mg, for which heat treatment processes and corrosion tests were carried out. It was presented herein grindability test results and metallographic examination, as well. Hardness of the treated alloys with those ones subjected to corrosion process were compared.

Laser, surface treatment, laser feeding, composite layer, wear resistance, aluminium alloys, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

In this work, the influence of a high power diode laser surface treatment on the structure and properties of aluminium alloy has been determined. The aim of this study was to improve the mechanical and tribological properties of the surface layer of the aluminium alloy by simultaneously melting and feeding tungsten carbide particles into the molten pool. During the process was used high-power diode laser HPDL. In order to remelt the aluminium alloy surface the HPDL laser of 1.8, 2.0 and 2.2 kW laser beam power has been used. The linear laser scan rate of the beam was set 0.5 cm/s. In order to protect the liquid metal during laser treatment was used argon. As a base material was used aluminium alloy ENAC-AlMg9. To improve the surface mechanical and wear properties of the applied aluminium alloy was used biphasic tungsten carbide WC/W2C. The size of alloying powder was in the range 110-210 µm. The ceramic powder was introduced in the remelting zone by a gravity feeder at a constant rate of 8 g/m.

Anodization, Surface Treatment, Alumina, Al2O3 layer, Aluminium alloys, Wear resitance, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

This paper presents the influence of casting method and anodic treatment parameters on thickness and structure of an anodic layer formed on aluminium alloys. As test materials was used the aluminium alloy AlSi9Cu3, which was adopted to the casting process and anodic treatment. In this paper are presented the wear test results and metallographic examination, as well as hardness of non-anodised and anodised alloys subjected to anodising process.

tool materials, surface treatment, laser, tribology, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

Investigations include alloying the PMHSS6-5-3 steel surface layer with carbide and ceramic powders WC, VC, TiC, SiC, Si3N4 and Al2O3, using the high power diode laser (HPDL). Laser treatment is especially promising for solving contemporary surface engineering problems making it possible to focus precisely the delivered energy in the form of heat in the surface layer. The structural mechanism was determined of surface layers development, effect was studied of alloying parameters, method on structure refinement and influence of these factors on the mechanical properties of surface layer, and especially on its abrasive wear resistance. The fine grained martensite structure is responsible for hardness increase of the alloyed layer. The tribological wear relationships were determined for laser treated surface layers, determining friction coefficient, and wear trace shape developed due to the abrasive wear of the investigated surfaces. Comparison of the laser treatment parameters and tribological properties of surface layer after remelting and alloying with hard particles of the PMHSS6-5-3 steel using the high power diode laser to obtain the optimum service properties is the outcome of the investigations carried out.

GRAPHENE synthesis, SULFURIC acid, NITRIC acid, X-ray diffraction measurement, and ATOMIC force microscopy

In this study, graphene was functionalized via acid oxidation in the presence of a mixture of concentrated sulfuric acid and nitric acid. The oxidized graphene was silanized using the coupling agent, 3-aminopropyltriethoxsilane, resulting in functionalized graphene. The oxidized graphene and functionalized graphene were characterized by X-Ray diffraction, Fourier transform infrared spectroscopy, High-resolution micro Raman spectroscopy, thermogravimetric analysis, and atomic force microscopy to confirm the presence of functional moieties on the graphene surface. Thermal studies also demonstrate that the functionalized material is thermally stable up to higher temperatures. [ABSTRACT FROM AUTHOR]

Graphite, Thermal Properties, Raman Spectroscopy, Surface Treatment, 3-APTES, Mining engineering. Metallurgy, TN1-997, Materials of engineering and construction. Mechanics of materials, and TA401-492

In this study, graphene was functionalized via acid oxidation in the presence of a mixture of concentrated sulfuric acid and nitric acid. The oxidized graphene was silanized using the coupling agent, 3-aminopropyltriethoxsilane, resulting in functionalized graphene. The oxidized graphene and functionalized graphene were characterized by X-Ray diffraction, Fourier transform infrared spectroscopy, High-resolution micro Raman spectroscopy, thermogravimetric analysis, and atomic force microscopy to confirm the presence of functional moieties on the graphene surface. Thermal studies also demonstrate that the functionalized material is thermally stable up to higher temperatures.

STEEL, MAGNESIUM, SURFACE preparation, SURFACE coatings, AUTOMOBILE industry, HEURISTIC programming, and QUANTITATIVE research

The purpose of the article is to present the results of comparative quantitative analysis of selected materials (steel, magnesium and aluminium alloys) and manufacturing technologies, to indicate their development outlooks and to present its application opportunities particularly in the automotive industry. Moreover in this article describes the application of the computer-integrated prediction of development for objectivised selection of a material and surface treatment technology, so that product properties can be achieved as are expected by a client. In a broad array of applications of the computer-integrated prediction of development in the field of material engineering, including materials surface engineering, experiment planning can be distinguished, usually including the selection of: a research material, surface treatment technology, construction solution and/or methods to review the final outcome achieved against the anticipated outcome. A material for the planned materials science experiments and its surface treatment technology, the application of which contributes most to meeting the high requirements set by a prospect product used, was selected in this work using a dendrological matrix of technology value. The dendrological matrix falls into to a group of contextual matrices allowing presenting graphically a quantitative assessment of the factor, phenomenon or process investigated while taking into account two analysis factors placed on the X and Y axis of the matrix. An evaluation classifying the three groups of materials analysed, i.e. casting magnesium alloys, casting aluminium alloys, constructional steels and their surface treatment technologies, to the individual quarters of the matrix was made based on the results of own materials science and heuristic experiments supported with a review of the literature. Considering the three groups of materials subjected to an expert assessment using a dendrological matrix being inherent part of materials surface engineering development prediction methods. Aluminium cast alloys has achieved here the best position. It was further demonstrated that laser treatment is a technology with the highest potential and attractiveness in the context of applying aluminium casting alloys for surface treatment. The metallographic examinations carried out give grounds to state that the ceramic powder alloying or feeding process will be carried out successfully in case of the aluminium alloy substrate, the powder particles will be distributed uniformly in the investigated surface layer, and that the particular layers is without cracks and failures and tightly adhere to the cast aluminium material matrix. With regard to the above, dynamic development achieved by exploitation of numerous application and development opportunities, especially strong prospects in the automotive industry, aviation industry, military sector, sport sector and in civil engineering is a recommended by appliance of long-term action strategy. [ABSTRACT FROM AUTHOR]