scholarly journals Effect of Pulsing Configuration and Magnetic Balance Degree on Mechanical Properties of CrN Coatings Deposited by Bipolar-HiPIMS onto Floating Substrate

Coatings ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1526
Author(s):  
Vasile Tiron ◽  
Mihai Alexandru Ciolan ◽  
Georgiana Bulai ◽  
Daniel Cristea ◽  
Ioana-Laura Velicu
Keyword(s):  
Mechanical Properties ◽  
Xrd Analysis ◽  
Type I ◽  
Ion Energy ◽  
Insulating Films ◽  
First Case ◽  
Unbalanced Magnetron ◽  
Hardness Values ◽  
Crn Coatings ◽  
Magnetic Balance

Despite its great potential for thin films deposition and technological applications, the HiPIMS technology has its own limitations including the control of ion energy and flux towards the substrate when coping with the deposition of electrical insulating films and/or the deposition onto insulating/electrically grounded substrates. The bipolar-HiPIMS has been recently developed as a strategy to accelerate the plasma ions towards a growing film maintained at ground potential. In this work, the benefits of bipolar-HiPIMS deposition onto floating or nonconductive substrates are explored. The effect of bipolar-HIPIMS pulsing configuration, magnetic balance-unbalance degree, and substrate’s condition on plasma characteristics, microstructure evolution, and mechanical properties of CrN coatings was investigated. During the deposition with a balanced magnetron configuration, a significant ion bombardment effect was detected when short negative pulses and relative long positive pulses were used. XRD analysis and AFM observations revealed significant microstructural changes by increasing the positive pulse duration, which results in an increase in hardness from 7.3 to 16.2 GPa, during deposition on grounded substrates, and from 4.9 to 9.4 GPa during the deposition on floating substrates. The discrepancies between the hardness values of the films deposited on floating substrates and those of the films deposited on grounded substrates become smaller/larger when a type I/type II unbalanced magnetron configuration is used. Their hardness ratio was found to be 0.887, in the first case, and 0.393, in the second one. Advanced application-tailored coatings can be deposited onto floating substrates by using the bipolar-HiPIMS technology if short negative pulses, relative long positive pulses together with type I unbalanced magnetron are concomitantly used.

Structural and Mechanical Properties of Multilayer TiN/CrN Coatings

2007 ◽  
Author(s):  
Manohar S. Konchady ◽  
Sergey Yarmolenko ◽  
Devdas M. Pai ◽  
Jag Sankar
Keyword(s):  
Mechanical Properties ◽  
Layer Thickness ◽  
Single Layer ◽  
Preferred Orientation ◽  
X Ray Diffraction ◽  
Unbalanced Magnetron Sputtering ◽  
Deposition Parameters ◽  
Unbalanced Magnetron ◽  
Crn Coatings ◽  
Modulation Wavelength

Multilayer and superlattice coatings of TiN/CrN coating are deposited on Si(100) substrate at different modulation wavelength by reactive unbalanced magnetron sputtering and characterized using X-ray diffraction, nanoindentation, AFM. Nano-roughness of films is in good correlation with hardness and modulus and this effect has been used for optimization of deposition parameters. Preliminary results have shown slightly better mechanical properties for multilayered TiN/CrN coatings compared to single layer TiN and CrN coatings. The XRD results have shown a preferred orientation in <100> direction for TiN/CrN multilayer coatings at modulation wavelengths below 80 nm. At 100 nm layer thickness, TiN revealed small amount of crystals with <111> orientation and their content significantly increases with increase in layer thickness while CrN layers only show preferred orientation of <100>. Multilayered coatings exhibit better mechanical properties due to presence of large number of interfaces which act as barrier to dislocations. Fracture toughness and tribological properties of these coatings are also expected to show significant improvement and the investigation in this area is under progress.

Effect of Temperature on Structure and Mechanical Properties of CrN Coatings Deposited by Closed Field Unbalanced Magnetron Sputtering

2013 ◽  
Vol 591 ◽  
pp. 190-193
Author(s):  
Hao Zhang ◽  
Shu Wang Duo ◽  
Xiang Min Xu ◽  
Ting Zhi Liu
Keyword(s):  
Mechanical Properties ◽  
Magnetron Sputtering ◽  
Grain Shape ◽  
Effect Of Temperature ◽  
Closed Field ◽  
Columnar Crystal ◽  
Crn Coating ◽  
Unbalanced Magnetron Sputtering ◽  
Unbalanced Magnetron ◽  
Crn Coatings

CrN coatings were fabricated by Closed Filed Unbalanced Magnetron Sputtering (CFUMS). The effect of substrate temperature (TS) on phase components, morphologies and mechanical properties of CrN coatings were studied. The results show that the phase in coatings, which has little to do with TS, was the coexistence of Cr, Cr2N and CrN. The grain shape of the columnar crystal CrN coating was the coexistence of pyramidal and plane topography. The hardness and adhension of CrN coating first increased with the rise of temperature, then decreased when the values of both them were constant ones. It has the highest hardness and bonding strength simultaneously at 300°C.

Improvement of the Mechanical Properties of Glasses Based on the 3CaO.P2O5-SiO2-MgO System after Heat-Treatment

2010 ◽  
Vol 636-637 ◽  
pp. 41-46 ◽  
Author(s):  
J.K.M.F. Daguano ◽  
Claudinei dos Santos ◽  
Paulo Atsushi Suzuki ◽  
Luiz A. Bicalho ◽  
Maria Helena F.V. Fernandes
Keyword(s):  
Mechanical Properties ◽  
Fracture Toughness ◽  
Glass Ceramics ◽  
Xrd Analysis ◽  
Phase Content ◽  
Heat Treated ◽  
Different Temperatures ◽  
Hardness Values ◽  
Crystallization Degree ◽  
Temperature Crystallization

Glasses based on the 3CaO.P2O5-SiO2-MgO system present high bioactivity aiming the use as bone restorations. On the other hand, the low mechanical properties reduce the importance of this glass aiming the use as restoration bulk specimens. In this work, glass-ceramics were obtained by devitrification of this glass using different temperatures. CaCO3, SiO2, MgO and Ca(H2PO4).H2O were used as starting-powders. Powder mixture was milled/homogenized and melted at 1600°C, for 2h and annealed at 700°C for 4h with cooling rate of 3°C/min. Glass specimens of 151550mm3 were characterized by DTA and XRD analysis. Specimens were heat-treated in different temperatures between 7000C and 1050°C, for 4 hours, obtaining glass-ceramics with different crystallized phase content. Hardness and fracture toughness were determined and correlated with crystalline phase content. The results indicated that crystallization-degree increase with the temperature, and the mechanical properties are improved: Hardness values present increases lower than 20% as function of the crystallization. Fracture toughness may increase 100% as function of temperature (crystallization degree).

Influence of Substrate Temperature and Bias Voltage on Structure and Mechanical Properties of CrN Coatings

2013 ◽  
Vol 591 ◽  
pp. 99-103 ◽  
Author(s):  
Hao Zhang ◽  
Shu Wang Duo ◽  
Xiang Min Xu ◽  
Huan Ke ◽  
Ting Zhi Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Substrate Temperature ◽  
Deposition Rate ◽  
Bias Voltage ◽  
High Deposition Rate ◽  
Properties Of Coatings ◽  
Unbalanced Magnetron ◽  
Magnetron Sputter ◽  
Influence Of Substrate ◽  
Crn Coatings

CrN coatings have been deposited successfully by Closed Filed Unbalanced Magnetron Sputter Ion Plating (CFUMSIP). The effect of substrate temperature (TS) and bias voltage (VB) together on microstructure, morphologies and mechanical properties of CrN coatings were studied. The results showed that the deposition rate of CrN coatings declines with the increase of VB Under both room temperature (R.M.) and 300°C. The FCC-CrN disappeared gradually and orth-CrN arised with the increase of VB, and the TS promoted the transformation from FCC - CrN to orth - CrN. The surface morphology of CrN coatings with changed VBs was greatly different, and VB could further improve the mechanical properties of coatings. In this paper, the CrN coating with the parameters (TS =300°C, VB =-30V) had relatively high deposition rate and mechanical properties.

Comparative Studies on Microstructure and Mechanical Properties of CrN, Cr-Mo-N and Cr-Si-N Coatings

2008 ◽  
Vol 569 ◽  
pp. 101-104 ◽  
Author(s):  
Ji Hwan Yun ◽  
Sung Kyu Ahn ◽  
Kwang Ho Kim
Keyword(s):  
Mechanical Properties ◽  
Comparative Studies ◽  
Wear Behavior ◽  
Microstructural Change ◽  
Maximum Hardness ◽  
Ion Plating ◽  
Microstructure And Mechanical Properties ◽  
Si Content ◽  
Hardness Values ◽  
Crn Coatings

CrN-based multi-component coatings were deposited by a hybrid coating system combining the arc ion plating (AIP) and sputtering technique. In this work, comparative studies on microstructure and mechanical properties of microhardness and wear behavior among CrN, Cr-Mo- N, Cr-Si-N coatings were systematically conducted. Adding Mo and Si atoms into CrN coatings had important effects on microstructural change and mechanical properties of CrN coatings. The maximum hardness values of Cr-Mo-N and Cr-Si-N coatings were the same value of 34GPa, These values were much enhanced compared with 18GPa of CrN coating. The average friction coefficient of CrN-based coatings decreased to 0.37 and 0.2 with the incorporation of Mo and Si content

Effect of N2 Flow Rate on Structure and Mechanical Properties of CrN Coatings Prepared by Closed Field Unbalanced Magnetron Sputtering

2013 ◽  
Vol 591 ◽  
pp. 95-98 ◽  
Author(s):  
Hao Zhang ◽  
Shu Wang Duo ◽  
Xiang Min Xu ◽  
Ting Zhi Liu
Keyword(s):  
Mechanical Properties ◽  
Magnetron Sputtering ◽  
Flow Rate ◽  
Closed Field ◽  
Nitrogen Flow ◽  
Columnar Crystal ◽  
Unbalanced Magnetron Sputtering ◽  
Unbalanced Magnetron ◽  
Crystal Preferred Orientation ◽  
Crn Coatings

CrN coatings were deposited by Closed Filed Unbalanced Magnetron Sputtering (CFUMS). The effect of N2 flow rate on composition, phase components, morphologies and mechanical properties of CrN coatings were studied. The results show that the deposition rate of CrN coatings declined with the increase of nitrogen flow percentage in a Ar/N2 mixture atmosphere. When the nitrogen flow percentage reached 50% or more, the Cr and N atomic ratio of CrN coatings is close to 1:1. The phase in coatings was the coexistence of Cr, Cr2N and CrN, but the crystal preferred orientation changed significantly with the different N2 flow rates. The columnar crystal CrN coating with low N2 flow rate was denser. The hardness and adhension of CrN coatings have no direct relationship with N2 flow rate.

Mechanical Properties and Oxidation Resistance of CrN Coatings Deposited by Closed Field Unbalanced Magnetron Sputter Ion Plating

2013 ◽  
Vol 591 ◽  
pp. 176-179 ◽  
Author(s):  
Hao Zhang ◽  
Shu Wang Duo ◽  
Xiang Min Xu ◽  
Fei Fei Luo ◽  
Ting Zhi Liu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Oxidation Resistance ◽  
High Temperature Oxidation ◽  
Closed Field ◽  
Temperature Oxidation ◽  
Ion Plating ◽  
Unbalanced Magnetron ◽  
Before And After ◽  
Magnetron Sputter ◽  
Crn Coatings

CrN coatings were prepared by Closed Filed Unbalanced Magnetron Sputter Ion Plating (CFUMSIP). The microstructure and morphologies of CrN coatings before and after oxidation were analyzed by XRD and SEM. At the same time, the mechanical properties and oxidation resistance of CrN coating were also studied. The results indicate that the phase in the dense CrN coatings with a hardness of 1979 HV and a adhension of 54 N was the coexistence of Cr, Cr2N and CrN. Besides, The CrN coatings showed good high-temperature oxidation resistance at 700°C while the coating failed at 800°C.

Micro-Hardness and Morphology of LDPE Influenced by Beta Radiation

2014 ◽  
Vol 606 ◽  
pp. 253-256 ◽  
Author(s):  
Martin Ovsik ◽  
Petr Kratky ◽  
David Manas ◽  
Miroslav Manas ◽  
Michal Stanek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Hardness Test ◽  
Polymer Materials ◽  
Beta Radiation ◽  
Micro Hardness ◽  
X Ray Diffraction ◽  
Depth Sensing ◽  
Surface Layers ◽  
Hardness Values ◽  
Different Doses

This article deals with the influence of different doses of Beta radiation to the structure and mico-mechanical properties of Low-density polyethylene (LDPE). Hard surface layers of polymer materials, especially LDPE, can be formed by radiation cross-linking by β radiation with doses of 33, 66 and 99 kGy. Material properties created by β radiation are measured by micro-hardness test using the DSI method (Depth Sensing Indentation). Individual radiation doses caused structural and micro-mechanical changes which have a significant effect on the final properties of the LDPE tested. The highest values of micro-mechanical properties were reached at radiation dose of 66 and 99 kGy, when the micro-hardness values increased by about 21%. The changes were examined and confirmed by X-ray diffraction.

scholarly journals The preparation and application of calcium phosphate biomedical composites in filling of weight-bearing bone defects

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lijia Cheng ◽  
Tianchang Lin ◽  
Ahmad Taha Khalaf ◽  
Yamei Zhang ◽  
Hongyan He ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Weight Bearing ◽  
Bone Defects ◽  
Type I ◽  
Artificial Bone ◽  
Thermosensitive Hydrogel ◽  
Bone Repairing ◽  
Histological Staining

AbstractNowadays, artificial bone materials have been widely applied in the filling of non-weight bearing bone defects, but scarcely ever in weight-bearing bone defects. This study aims to develop an artificial bone with excellent mechanical properties and good osteogenic capability. Firstly, the collagen-thermosensitive hydrogel-calcium phosphate (CTC) composites were prepared as follows: dissolving thermosensitive hydrogel at 4 °C, then mixing with type I collagen as well as tricalcium phosphate (CaP) powder, and moulding the composites at 37 °C. Next, the CTC composites were subjected to evaluate for their chemical composition, micro morphology, pore size, Shore durometer, porosity and water absorption ability. Following this, the CTC composites were implanted into the muscle of mice while the 70% hydroxyapatite/30% β-tricalcium phosphate (HA/TCP) biomaterials were set as the control group; 8 weeks later, the osteoinductive abilities of biomaterials were detected by histological staining. Finally, the CTC and HA/TCP biomaterials were used to fill the large segments of tibia defects in mice. The bone repairing and load-bearing abilities of materials were evaluated by histological staining, X-ray and micro-CT at week 8. Both the CTC and HA/TCP biomaterials could induce ectopic bone formation in mice; however, the CTC composites tended to produce larger areas of bone and bone marrow tissues than HA/TCP. Simultaneously, bone-repairing experiments showed that HA/TCP biomaterials were easily crushed or pushed out by new bone growth as the material has a poor hardness. In comparison, the CTC composites could be replaced gradually by newly formed bone and repair larger segments of bone defects. The CTC composites trialled in this study have better mechanical properties, osteoinductivity and weight-bearing capacity than HA/TCP. The CTC composites provide an experimental foundation for the synthesis of artificial bone and a new option for orthopedic patients.

scholarly journals Mineralogical Composition and Physical–Mechanical Properties of Dasht-E-Taatrang Zar Sand Deposits (Afghanistan)

2020 ◽  
Vol 5 (1) ◽  
pp. 2
Author(s):  
Hemayatullah Ahmadi ◽  
Atal Yousufi ◽  
Amir Mohammad Mosazai
Keyword(s):  
Mechanical Properties ◽  
Construction Material ◽  
Mineralogical Composition ◽  
Xrd Analysis ◽  
Sample Collection ◽  
Extensive Field ◽  
Chemical And Mineralogical Composition ◽  
New City ◽  
Two Phases ◽  
Field Works

Sand is a common construction material used for various purposes, e.g., concrete, mortar, render, screed, and asphalt. The usage depends on its fineness, and its fineness is controlled by its mineralogical composition and physical-mechanical properties. This research aims to determine the chemical and mineralogical composition and the physical-mechanical properties of the Dasht-e-Taatrang Zar sand deposits within the Qarabagh and Bagram districts of Kabul and Parwan provinces in Afghanistan. To achieve the objectives of this research, a review of the existing literature has been combined with new extensive field works for macroscopic studies and sample collection, and laboratory analyses. In total, 23 samples during two phases of field works were collected and subjected to lab works for XRF, Schlich, and XRD analysis to determine the chemical and mineralogical composition; moreover, sieve and Atterberg analysis, specific gravity, soundness, and alkali-silica reaction tests were performed for characterization of the physical-mechanical properties of the studied samples. The results of the tests show that the Taatrang Zar sand deposits are considered as a suitable construction material, and due to their simple accessibility, the deposits have high potential as a construction material supplier for the Kabul new city project (Dehsabz) in Kabul and adjacent Parwan and Kapisa provinces.

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