The Experts below are selected from a list of 108 Experts worldwide ranked by ideXlab platform
V. R. Howes - One of the best experts on this subject based on the ideXlab platform.
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Indentation creep measurements using a Rockwell hardness Tester
Journal of Materials Science, 1991Co-Authors: V. R. HowesAbstract:A Rockwell superficial hardness Tester has been used to continuously monitor hardness under load with time. An analysis of the Rockwell Test, that showed the relationship between the measured parameters and the on-load hardness and elastic recovery has been quantitatively verified.
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Indentation creep measurements using a Rockwell hardness Tester
Journal of Materials Science, 1991Co-Authors: V. R. HowesAbstract:A Rockwell superficial hardness Tester has been used to continuously monitor hardness under load with time. An analysis of the Rockwell Test, that showed the relationship between the measured parameters and the on-load hardness and elastic recovery has been quantitatively verified. Low homologous temperature, high stress, indentation creep in the macrohardness range has been measured for aluminium, copper and mild steel, but was not detectable for brass and silver steel. The stress relaxation was no more than 10% and appeared to follow an exponential decay to an equilibrium value. The difference between normal uniform tensile creep and indentation creep, and explanations for the latter, have been discussed, and the measured relaxation time has been related to a ratio of elastic and creep indentation material constants. Bearing in mind the world-wide availability of Rockwell hardness Testers, it is suggested that this extension to creep Testing, and possibly fatigue Testing, may be a useful development for industrial non-destructive quality control and specification checking of materials and components.
Adam Gilewicz - One of the best experts on this subject based on the ideXlab platform.
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The influence of the MCVA deposition parameters on the structure and tribological properties of DLC coatings on woodworking HSS tool substrates
Archives of materials science and engineering, 2013Co-Authors: M. Pancielejko, Andrzej Czyżniewski, Adam Gilewicz, W Szymanski, V. ZavaleyevAbstract:Purpose: The purpose of the present study was the influence of deposition parameters of diamondlike-carbon coatings (DLC), with the modified cathodic vacuum arc (MCVA) method deposited on tool substrates (high-speed steel HS6-5-2) for woodworking, on their structure and tribological properties. Design/methodology/approach: DLC coating was deposited by MCVA method. Structure, adhesion, hardness, internal stresses and friction wear resistance of DLC coatings were Tested. Tests of knives coated with DLC and uncoated ones was made by machining medium density fibreboard (MDF) using a industrial milling machine. Findings: The hardness of DLC coatings was 22.7-57.1 GPa. The Raman spectrum of DLC coatings was analysed The high hardness and internal stresses of DLC coating is related to the amount of sp3 bonds. DLC coatings display high adhesion: critical load in the scratch method (LC2 = 22-40 N), from Rockwell Test (HF1). The influence of the structure, hardness and adhesion of coatings on wear resistance of coated tools is discussed. Practical implications: The wide range of tribological properties of DLC coatings that are deposited with different parameters may indicate the possibility of their application for tools for wood-like materials in order to increase their durability. Originality/value: Depending of the deposition parameters applied, it is possible to obtain DLC coatings in a wide range of hardness (22.7-57.1 GPa) and adhesion (LC2 = 22-40 N). The industrial Tests of cutting wood-based materials indicate that the DLC coatings with different properties improve HSS tool performance. The DLC coatings show antiwear properties required in industry application. The DLC coatings might be apply on high-speed steel planer knives for woodworking industry.
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The cutting properties and wear of the knives with DLC and W-DLC coatings, deposited by PVD methods, applied for wood and wood-based materials machining
Archives of materials science and engineering, 2012Co-Authors: M. Pancielejko, Andrzej Czyżniewski, Adam Gilewicz, V. Zavaleyev, W SzymanskiAbstract:Purpose: Performance of DLC and W-DLC coated woodworking knives was investigated. The results of Testing DLC and W-DLC coating properties as well as the results of life-time Tests in the form of wear of HSS and HM knives with these coatings is presents. Design/methodology/approach: DLC coating was deposited by MCVA method, and W-DLC coating was deposited by pulsed RMS. Tests of knives coated with DLC and W-DLC as uncoated ones was made by machining: MDF board, pinewood slats and floorboard - using a typical industrial milling machine. Findings: DLC coating is significantly harder (33-40 GPa) than W-DLC coating (19 GPa). From Rockwell Test it can be concluded that both coatings display high adhesion (HF1), whereas in the scratch methods, significantly lower adhesion of DLC coating can be observed (LC2 = 17-21 N) in comparison to W-DLC coating (LC2 = 54 N). Influence of the hardness and adhesion of coatings on wear resistance of coated tools is discussed. Practical implications: Wear resistance of planer knives coated with DLC is by approx. 20%, and W-DLC by approx. 30% higher in comparison with uncoated knives during MDF milling. Wear of planer knives with W-DLC coating is approx. by 10%, and DLC by approx. 25% lower in comparison to uncoated HSS knives during pinewood milling. Lifetime of HM shape tools coated DLC and W-DLC is considerably higher (200-300 %) during floorboard milling. Originality/value: The industrial Tests of cutting wood and wood-based materials indicate that the carbon coatings deposited on the tool generally improve its performance and all wear indexes for the tools are lower than for uncoated. The DLC and W-DLC coatings show good antiwear properties required in industry application.
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The Properties of Multilayer CrCN/CrN Coatings Dependent on Their Architecture
Plasma Processes and Polymers, 2011Co-Authors: Bogdan Warcholiński, Adam GilewiczAbstract:CrN based multilayer coatings are possible replacements for chromium nitride monolayer coating because of their good mechanical and chemical properties. This paper reports an investigation of CrCN/CrN coatings deposited on HS6-5-2 steel substrate using cathodic arc evaporation. The investigated coatings of the total thickness of ca. 2.5 μm were composed of six bilayers, each of them with alternating CrCN and CrN layers. The thickness of the bilayer was ca. 400 nm and the ratio of layer thickness partition (CrCN/CrN) was 1:5, 1:2 and 1:1. The chemical composition was determined with the EDS method. The microstructure of thin films was examined with the SEM. A micro Vickers hardness Tester and pin-on-disc wear Tests were used to determine the hardness and tribological properties of the coatings: the coefficient of the friction and wear rate. In order to assess the adhesion of the coatings to the substrate, the scratch Test and Rockwell Test were applied. All the coatings investigated are characterized by a good adhesion which decreases with the rise of the CrCN layer thickness in the bilayer. When the CrCN layer thickness in bilayer rises, the hardness and compressive stress increase, but the wear rate decreases.
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Anti-wear multilayer coatings based on chromium nitride for wood machining tools
Wear, 2010Co-Authors: Adam Gilewicz, Bogdan Warcholiński, P. Myslinski, W SzymanskiAbstract:Abstract The performed experiments revealed that the anti-wear resistance of chromium nitride and chromium carbonitride multilayer coatings obtained by the PVD method was higher than each of the phases separately. The CrN/CrCN coatings were obtained using cathodic arc evaporation. They consisted of seven modules, each approximately 400 nm thick, characterised by different thickness ratio of the CrN and CrCN layers in the modulus. A layer of chromium 0.1 μm thick was used as a sublayer. The adhesion of the coatings was determined using scratch Test and Rockwell Test. Hardness and stress as well as friction and wear coefficients when used to work timber were determined. Industrial milling Tests of dry wood were carried out. The results of above measurements showed that the best useful properties were observed when the thickness ratio in coatings’ module was 2:1 which could be attributed to its very good adhesion to the substrate (about 115 N) and low wear rate. The tools with multilayer CrN/CrCN coatings improve the quality of the treated wood surface in comparison with uncoated knives.
Bogdan Warcholiński - One of the best experts on this subject based on the ideXlab platform.
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The Properties of Multilayer CrCN/CrN Coatings Dependent on Their Architecture
Plasma Processes and Polymers, 2011Co-Authors: Bogdan Warcholiński, Adam GilewiczAbstract:CrN based multilayer coatings are possible replacements for chromium nitride monolayer coating because of their good mechanical and chemical properties. This paper reports an investigation of CrCN/CrN coatings deposited on HS6-5-2 steel substrate using cathodic arc evaporation. The investigated coatings of the total thickness of ca. 2.5 μm were composed of six bilayers, each of them with alternating CrCN and CrN layers. The thickness of the bilayer was ca. 400 nm and the ratio of layer thickness partition (CrCN/CrN) was 1:5, 1:2 and 1:1. The chemical composition was determined with the EDS method. The microstructure of thin films was examined with the SEM. A micro Vickers hardness Tester and pin-on-disc wear Tests were used to determine the hardness and tribological properties of the coatings: the coefficient of the friction and wear rate. In order to assess the adhesion of the coatings to the substrate, the scratch Test and Rockwell Test were applied. All the coatings investigated are characterized by a good adhesion which decreases with the rise of the CrCN layer thickness in the bilayer. When the CrCN layer thickness in bilayer rises, the hardness and compressive stress increase, but the wear rate decreases.
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Anti-wear multilayer coatings based on chromium nitride for wood machining tools
Wear, 2010Co-Authors: Adam Gilewicz, Bogdan Warcholiński, P. Myslinski, W SzymanskiAbstract:Abstract The performed experiments revealed that the anti-wear resistance of chromium nitride and chromium carbonitride multilayer coatings obtained by the PVD method was higher than each of the phases separately. The CrN/CrCN coatings were obtained using cathodic arc evaporation. They consisted of seven modules, each approximately 400 nm thick, characterised by different thickness ratio of the CrN and CrCN layers in the modulus. A layer of chromium 0.1 μm thick was used as a sublayer. The adhesion of the coatings was determined using scratch Test and Rockwell Test. Hardness and stress as well as friction and wear coefficients when used to work timber were determined. Industrial milling Tests of dry wood were carried out. The results of above measurements showed that the best useful properties were observed when the thickness ratio in coatings’ module was 2:1 which could be attributed to its very good adhesion to the substrate (about 115 N) and low wear rate. The tools with multilayer CrN/CrCN coatings improve the quality of the treated wood surface in comparison with uncoated knives.
Diete Schneide - One of the best experts on this subject based on the ideXlab platform.
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a comparative study of adhesion Test methods for hard coatings
Surface & Coatings Technology, 1999Co-Authors: H Ollendorf, Diete SchneideAbstract:Abstract The feasibility of seven techniques for Testing and evaluating the adhesion of thin films was investigated: scratch Test, four-point bending Test, Rockwell Test, cavitation Test, impact Test, laser-acoustics and acoustic microscopy. The studies were performed with TiN films (thickness 1.2–2.45 μm) deposited on the annealed steel 42CrMo4. The adhesion of the TiN films was varied by varying the time of pre-sputtering the steel substrate with argon ions before the film deposition. Argon pre-sputtering for 15 min is recommended to guarantee an optimal adhesion. The pre-sputtering time, tS, was reduced down to 0.5 min to reduce the adhesion. The following Test parameters were used to evaluate the adhesion: the friction work, acoustic emission activity and critical load of the scratch Test, the critical strain and the defect density of the four-point bending Test, the proportional damage area of cavitation Test, the critical number of loading cycles of the impact Test, and Young's modulus of the film measured with the laser-acoustic method. These Test parameters were examined for any correlation with the pre-sputtering time, tS. The results are summarized in a table that shows which Test methods and Test parameters yield corresponding and contradictory evaluations of the film quality. The effect of defect density and residual stresses is discussed. Laser-acoustics and acoustic microscopy are non-destructive methods. Young's modulus, as measured by laser-acoustics, is sensitive to the density of micro-defects. This is expected to indicate their effect on the adhesion.
Yusuf Umardani - One of the best experts on this subject based on the ideXlab platform.
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Identifikasi Sifat Mekanik dan Struktur Mikro Material RingPiston Sepeda Motor Honda Supra X
2009Co-Authors: Lilik Supriyanto, A.priharyoto Bayuseno, Yusuf UmardaniAbstract:Piston Ring is one of the motor cycle components, which attach around piston head in burning room. Generally, four strokes motor cycle piston ring consist of three components, those are compression rings, including top ring and second ring. The compression rings work to enlarge machine compression at compression step, as well as to prevent cylinder contact with piston to make tolerance. The function of oil ring, which is to protect lubricating oil, doesn’t come over to cylinder wall into Combustion chamber. This research is done at compression rings (top ring) to know hardness value between piston ring of Honda Supra X which still newly and piston ring of Honda Supra X which have been used previously. Beside of hardness Test, it is also done micrographic Test to know micro structure type in new piston ring and also secondhand piston ring. The examination is at the room temperature. The result of the hardness Test using Rockwell Test method, which diamond as an indenter, mayor load 60 kg, shows that the new piston ring has hardness number 38,2 HRC. The secondhand piston ring has hardness number 32,95 HRC. Micrographic Test shows that the micro structure consists of ferrite and cemented. Keywords: Piston ring Honda Supra X, Hardness number, Micro Structure, Tensile Strength
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Karakteristik Material Ring Piston Honda Supra X Dibawah Pengaruh Thermal Cycling
2009Co-Authors: Eko Yuliyanto, A.priharyoto Bayuseno, Yusuf UmardaniAbstract:Piston Ring is one of the motor cycle components, which attach around piston head in burning room. Generally, four strokes motor cycle piston ring consist of three components, those are compression rings, including top ring and second ring. The compression rings work to enlarge machine compression at compression step, as well as to prevent cylinder contact with piston to make tolerance. The function of oil ring, which is to protect lubricating oil, doesn’t come over to cylinder wall into Combustion chamber. This research is done at compression rings (top ring) to know hardness value between piston ring of Honda Supra X which still newly and piston ring of Honda Supra X which have been used previously. Beside of hardness Test, it is also done micrographic Test to know micro structure type in new piston ring and also secondhand piston ring. The examination is at the room temperature. The result of the hardness Test using Rockwell Test method, which diamond as an indenter, mayor load 60 kg, shows that the new piston ring has hardness number 38,2 HRC. The secondhand piston ring has hardness number 32,95 HRC. Micrographic Test shows that the micro structure consists of ferrite and cemented. Keywords: Piston ring Honda Supra X, Hardness number, Micro Structure, Tensile Strength
