Reinforcing Glaze Layer of Restorative Dental Zirconia by Adding Nano Alumina Ceramics

The objective of this work is to study the effect of adding varying ratios of Nano Alumina to the glazing powder on glazing layer of restorative dental ceramic. The effect of addition is examined by applying Vickers hardness and surface roughness tests on the glazing layer. The specimens have been cut in a cubic form. The specimens were placed in the furnace for sintering up to temperature of 1450 oC. One specimen is glazed with glazing materials and the remaining three specimens are glazed with glazing materials but supported with varying ratios of Nano Alumina (10, 15 and 25 wt%) and all these specimens sintered at 850 oC. It was found that Vickers hardness is increased with increasing the ratios of Nano Alumina but the surface roughness decreased with increasing the ratios of Nano Alumina. Weibull modulus increased with Alumina additive increases for glass coating layer.

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On the Relevance of Volumetric Energy Density in the Investigation of Inconel 718 Laser Powder Bed Fusion

Materials ◽

10.3390/ma13030538 ◽

2020 ◽

Vol 13 (3) ◽

pp. 538 ◽

Cited By ~ 6

Author(s):

Fabrizia Caiazzo ◽

Vittorio Alfieri ◽

Giuseppe Casalino

Keyword(s):

Surface Roughness ◽

Energy Density ◽

Process Parameters ◽

Vickers Hardness ◽

Powder Bed Fusion ◽

Processing Conditions ◽

Laser Powder Bed Fusion ◽

Powder Bed ◽

Fractional Density ◽

Experimental Variation

Laser powder bed fusion (LPBF) can fabricate products with tailored mechanical and surface properties. In fact, surface texture, roughness, pore size, the resulting fractional density, and microhardness highly depend on the processing conditions, which are very difficult to deal with. Therefore, this paper aims at investigating the relevance of the volumetric energy density (VED) that is a concise index of some governing factors with a potential operational use. This paper proves the fact that the observed experimental variation in the surface roughness, number and size of pores, the fractional density, and Vickers hardness can be explained in terms of VED that can help the investigator in dealing with several process parameters at once.

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Plasma-resistant characteristics according to sintering conditions of CaO–Al2O3–SiO2 glass coating layer

Journal of the Korean Ceramic Society ◽

10.1007/s43207-021-00149-x ◽

2021 ◽

Author(s):

Yoon Sung Jung ◽

Kyung Won Min ◽

Jae Ho Choi ◽

Ji Sob Yoon ◽

Won Bin Im ◽

...

Keyword(s):

Coating Layer ◽

Glass Coating ◽

Sio2 Glass ◽

Sintering Conditions

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Accelerated Aging Effects on Surface Hardness and Roughness of Lingual Retainer Adhesives

The Angle Orthodontist ◽

10.2319/112106-473.1 ◽

2008 ◽

Vol 78 (1) ◽

pp. 140-144 ◽

Cited By ~ 16

Author(s):

Sabri Ilhan Ramoglu ◽

Serdar Usumez ◽

Tamer Buyukyilmaz

Keyword(s):

Surface Roughness ◽

Vickers Hardness ◽

Statistical Significance ◽

Accelerated Aging ◽

Aging Effects ◽

Surface Microhardness ◽

Halogen Light ◽

Before And After ◽

The Mean ◽

Lingual Retainer

Abstract Objective: To test the null hypothesis that accelerated aging has no effect on the surface microhardness and roughness of two light-cured lingual retainer adhesives. Materials and Methods: Ten samples of light-cured materials, Transbond Lingual Retainer (3M Unitek) and Light Cure Retainer (Reliance) were cured with a halogen light for 40 seconds. Vickers hardness and surface roughness were measured before and after accelerated aging of 300 hours in a weathering tester. Differences between mean values were analyzed for statistical significance using a t-test. The level of statistical significance was set at P < .05. Results: The mean Vickers hardness of Transbond Lingual Retainer was 62.8 ± 3.5 and 79.6 ± 4.9 before and after aging, respectively. The mean Vickers hardness of Light Cure Retainer was 40.3 ± 2.6 and 58.3 ± 4.3 before and after aging, respectively. Differences in both groups were statistically significant (P < .001). Following aging, mean surface roughness was changed from 0.039 μm to 0.121 μm and from 0.021 μm to 0.031 μm for Transbond Lingual Retainer and Light Cure Retainer, respectively. The roughening of Transbond Lingual Retainer with aging was statistically significant (P < .05), while the change in the surface roughness of Light Cure Retainer was not (P > .05). Conclusions: Accelerated aging significantly increased the surface microhardness of both light-cured retainer adhesives tested. It also significantly increased the surface roughness of the Transbond Lingual Retainer.

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Electrospray and Thermal Treatment Process for Enhancing Surface Roughness of Fecralloy Coating Layer on a Large Sized Substrate

Journal of Korean Powder Metallurgy Institute ◽

10.4150/kpmi.2017.24.1.46 ◽

2017 ◽

Vol 24 (1) ◽

pp. 46-52

Author(s):

Hye Moon Lee ◽

Hye Young Koo ◽

Sangsun Yang ◽

Dahee Park ◽

Sooho Jung ◽

...

Keyword(s):

Surface Roughness ◽

Thermal Treatment ◽

Treatment Process ◽

Coating Layer

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The Effect of the Electrical Discharge Machining Process on the Material Properties of Nonconductive Ceramics

Journal of Micro and Nano-Manufacturing ◽

10.1115/1.4032155 ◽

2016 ◽

Vol 4 (1) ◽

Cited By ~ 2

Author(s):

Nirdesh Ojha ◽

Florian Zeller ◽

Claas Mueller ◽

Holger Reinecke

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Flexural Strength ◽

Vickers Hardness ◽

Electrical Discharge ◽

High Performance ◽

Electrical Discharge Machining ◽

Machining Process ◽

Hardness Increase ◽

Edm Process

Electrical discharge machining (EDM) is widely used to manufacture complex shaped dies, molds and critical parts in conductive materials. With the help of an assisting electrode (AE), EDM process can be used to machine nonconductive ceramics. This paper evaluates the mechanical properties of three high-performance nonconductive ceramics (ZrO2, Si3N4, and SiC) that have been machined with the EDM process using AE. Mechanical properties such as Vickers hardness (HV 0.3), surface roughness (Sq), and flexural strength of the machined and the nonmachined samples are compared. The EDM process causes decrease in Vickers hardness, increase in surface roughness, and decrease in flexural strength.

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Optimization of Coated SiC Belt Grinding of Alumina Ceramics

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.76-78.38 ◽

2009 ◽

Vol 76-78 ◽

pp. 38-42 ◽

Cited By ~ 1

Author(s):

Xavier Kennedy ◽

S. Gowri

Keyword(s):

Surface Roughness ◽

Material Removal ◽

High Hardness ◽

Surface Damage ◽

High Temperature Strength ◽

Structural Ceramics ◽

Alumina Ceramics ◽

Belt Grinding ◽

Grinding Parameters ◽

Surface Damages

Advanced structural ceramics have been increasingly used in automotive, aerospace, military, medical and other applications due to their high temperature strength, low density, thermal and chemical stability. However, the Grinding of advanced ceramics such as alumina is difficult due to its low fracture toughness and sensitivity to cracking, high hardness and brittleness. In this paper, surface integrity and material removal mechanisms of Alumina ceramics ground with SiC abrasive belts, have been investigated. The surface damage have been studied with scanning electron microscope (SEM). The significance of grinding parameters on the responses was evaluated using Signal to Noise ratios.This research links the surface roughness and surface damages to grinding parameters. The optimum levels for maximum material removal and surface roughness been discussed.

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Effect of Ni and Zn Elements on the Microstructure and Antibacterial Properties of Cu Coatings

Journal of Engineering Materials and Technology ◽

10.1115/1.4044265 ◽

2019 ◽

Vol 142 (1) ◽

Author(s):

Khaled S. Al-Athel ◽

Najat Marraiki ◽

Abul Fazal M. Arif ◽

Syed Sohail Akhtar ◽

Javad Mostaghimi ◽

...

Keyword(s):

Surface Roughness ◽

Bacterial Adhesion ◽

316L Stainless Steel ◽

Coating Layer ◽

Antibacterial Properties ◽

Lower Surface ◽

Distilled Water ◽

Gram Positive ◽

Gram Negative ◽

E Coli

In this work, 316L stainless steel samples were coated with copper (Cu) and German silver (Cu 17%Ni 10%Zn) to investigate the relation between their mechanical and antibacterial behaviors. The mechanical and material characteristics of the samples were studied by looking into the microstructure of the surface and the cross-section of the coatings, the surface roughness, and the adhesion strength between the coating layer and the substrate. The antibacterial behavior is then studied against gram-negative Escherichia coli and gram-positive Staphylococcus aureus. Two experiments were conducted to examine the antibacterial behavior. In the first experiment, the coated samples were covered with distilled water, whereas in the second experiment, the samples were tested without being covered with distilled water. The results show that German silver (Cu 17%Ni 10%Zn) had a higher antibacterial rate than copper (Cu) by around 10% for both gram-negative E. coli and gram-positive S. aureus. The reason is because a smoother surface is expected to limit the bacterial adhesion in most cases, and the German silver samples have a lower surface roughness (Ra) due to the higher thermal expansion value of zinc (Zn) compared with copper (Cu). A more in-depth look into the effect of various thickness of the coating with alloying elements (in this case nickel and zinc) on the antibacterial rate would be of great interest.

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Nitrogen Ions Implantation in W-Based Quad Alloy: Structure, Electrical Resistivity, Surface Roughness and Vickers Hardness as a Function of Ion Dose

Metals and Materials International ◽

10.1007/s12540-020-00861-z ◽

2020 ◽

Cited By ~ 1

Author(s):

Muhammad Zakria Butt ◽

Dilawar Ali ◽

Muzamil Aftab ◽

Farooq Bashir ◽

M. Shahid Pervaiz ◽

...

Keyword(s):

Surface Roughness ◽

Electrical Resistivity ◽

Vickers Hardness ◽

Alloy Structure ◽

Ions Implantation ◽

Nitrogen Ions

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Comparative Evaluation of Mechanical Properties and Wear Ability of Five CAD/CAM Dental Blocks

Materials ◽

10.3390/ma12142252 ◽

2019 ◽

Vol 12 (14) ◽

pp. 2252 ◽

Cited By ~ 2

Author(s):

Yin ◽

Jang ◽

Lee ◽

Bae

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Vickers Hardness ◽

Computer Aided Design ◽

Filler Content ◽

Machined Surface ◽

Volume Percentage ◽

Computer Aided ◽

Cad Cam ◽

Aided Design

This study compares the mechanical properties and wear ability of five CAD/CAM (computer-aided design/computer-aided manufacturing) millable dental blocks. All the discs, including Amber Mill Hybrid, Vita Enamic, Katana Avencia, Lava Ultimate, and Amber Mill, were cut in dimensions of 1.2 mm in thickness and 12 mm in diameter, polished to a machined surface, and immersed in distilled water for seven days. Vickers hardness was measured and the indentations were observed using microscope. The discs were brushed under a 150 g load. Mean surface roughness (Ra) and topography were determined after 100,000 cycles. Finally the biaxial flexure strength of the discs was measured and the broken surfaces were observed using scanning electron microscopy (SEM). The data was subjected to Weibull analysis. All data were analyzed by one-way analysis (ANOVA). The results of Vickers hardness are shown as: Amber Mill > Vita Enamic > Amber Mill Hybrid > Lava Ultimate > Katana Avencia. Katana Avencia showed the highest volume percentage reduction and the roughest surface after toothbrushing. The biaxial flexural strength is shown as: Amber Mill > Katana Avencia > Lava Ultimate > Amber Mill Hybrid > Vita Enamic. All the tested materials exhibited varying degrees of mass loss and surface roughness. The properties of the composite materials are related to the filler content, filler volume, and polymerization methods.

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