Thin Films Deposition of Ta2O5 and ZnO by E-Gun Technology on Co-Cr Alloy Manufactured by Direct Metal Laser Sintering

In recent years in the dental field, new types of materials and techniques for the manufacturing of dental crowns and analog implants have been developed to improve the quality of these products. The objective of this article was to perform the surface characterization and determine the properties of Co-Cr alloy samples fabricated by the direct metal laser sintering (DMLS) process and coated by e-gun technology with thin films of Ta2O5 and ZnO. Both oxides are frequently used for dental products, in pharmacology, cosmetics, and medicine, due to their good anticorrosive, antibacterial, and photo-catalytic properties. Following the deposition of thin oxide films on the Co-Cr samples fabricated by DMLS, a very fine roughness in the order of nanometers was obtained. Thin films deposition was realized to improve the hardness and the roughness of the Co-Cr parts fabricated by the DMLS process. Surface characterization was performed using SEM-EDS, AFM, and XRD. AFM was used to determine the roughness of the samples and the nanoindentation curves were determined to establish the hardness values and modulus of elasticity.

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INFLUENCE OF GRINDING PROCESS OF PLATES FOR DENTAL CROWNS MANUFACTURING BY DIRECT METAL LASER SINTERING

17th International Multidisciplinary Scientific GeoConference SGEM2017, Nano, Bio and Green � Technologies for a Sustainable Future ◽

10.5593/sgem2017/61/s25.100 ◽

2017 ◽

Author(s):

Diana-Irinel Diana-Irinel

Keyword(s):

Laser Sintering ◽

Grinding Process ◽

Direct Metal Laser Sintering ◽

Dental Crowns

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Numerical Modeling of Non-linear Thermal Stress in Direct Metal Laser Sintering Process of Titanium Alloy Products

Proceeding of First Thermal and Fluids Engineering Summer Conference ◽

10.1615/tfesc1.iam.012685 ◽

2016 ◽

Cited By ~ 2

Author(s):

Xinran Zhao ◽

Patcharapit Promoppatum ◽

Shi-Chune Yao

Keyword(s):

Numerical Modeling ◽

Titanium Alloy ◽

Thermal Stress ◽

Laser Sintering ◽

Sintering Process ◽

Direct Metal Laser Sintering ◽

Non Linear

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Pengaruh Tekanan dan Penggunaan Conplast terhadap Sifat Mekanik Eternit dari Abu Cangkang Sawit

Jurnal Riset Teknologi Industri ◽

10.26578/jrti.v8i15.1552 ◽

2016 ◽

Vol 8 (15) ◽

pp. 47-54

Author(s):

Haspiadi Haspiadi

Keyword(s):

Mechanical Properties ◽

Oil Palm ◽

Modulus Of Elasticity ◽

Modulus Of Rupture ◽

Palm Shell ◽

Oil Palm Shell ◽

Density Values ◽

Test Result

The purpose of this research is to know the influence of pressure and use of conplast against mechanical properties which are a Modulus of Elasticity (MOE) and Modulus of Rupture (MOR) of plasterboard. The study is done because still low quality of plasterboard made from a mixture of ashes of oil-palm shell especially of the mechanical properties compared to the controls. The method of this reserach used variation of printed pressure and the addition of conplast. Test result is obtained that the highest value of Modulus of Elasticity (MOE) 90875.94 Kg/cm2, Modulus of Rupture (MOR) 61.16 Kg/cm2 and density values in generally good printed at the pressure 60 g/cm3 and the addition of conplast 25% as well as the composition of the ash of palm shell oil 40%: limestone 40%: cement 15%: fiber 5% and 300 mL of water. ABSTRAK Tujuan dari penelitian ini adalah untuk mengetahui pengaruh tekanan dan penggunaan conplast terhadap sifat mekanik yaitu kuat lentur dan keteguhan patah eternit berbahan dasar abu cangkang sawit. Penelitian ini dilakukan karena masi rendahnya mutu eternit berbahan campuran abu cangkang sawit dari bolier khususnya sifat mekanik dibandingkan dengan kontrol. Metode penelitian yang digunakan adalah dengan variasi tekanan cetak dan penambahan conplast. Hasil uji diperoleh bahwa kuat lentur tertinggi sebesar 90875,94 Kg/cm2 dan keteguhan patah sebesar 61,16 Kg/cm2, yang dicetak pada tekanan 60 g/cm3 dan penambahan conplast 25% dengan komposisi abu cangkang sawit 40 %: kapur 40 % : semen 15 %: serat 5 % dan air 300 mL.Kata Kunci : Abu cangkang sawit, conplast, kuat lentur, keteguhan patah.

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ANALYSIS OF SOUND SPEED IN LONGITUDINAL DIRECTION AT REFERENCE MOISTURE CONTENT (w = 12 %) IN SAWMILL ASSORTMENTS (FAGUS SYLVATICA, L.)

Akustika ◽

10.36336/akustika20203745 ◽

2020 ◽

pp. 45-50

Author(s):

Alena Rohanová

Keyword(s):

Moisture Content ◽

Modulus Of Elasticity ◽

Dynamic Modulus ◽

Sound Speed ◽

Longitudinal Direction ◽

Structural Timber ◽

Sound Speeds ◽

Dynamic Modulus Of Elasticity ◽

Round Timber

This paper explores the analysis of sound speeds in the longitudinal direction and their reduction to the reference moisture content w = 12 %. The sound speed cw was determined with Sylvatest Duo device. Moisture content of beech sawmill assortments (round timber: N = 16, logs: N = 2 × 16, structural boards: N = 54) in the range of 12 – 72 % was measured. For the analysis purposes, the sound speed was converted to reference conditions (c12, uref = 12%). A second-degree polynomial (parabola) with a regression equation of the form: c// = 5649 - 27,371 × w + 0.0735 × w2 was used to convert cw to c12, and correction of measured and calculated values was used as well. The sound speeds c12 in sawmill assortments (c12,round, c12,log, c12,board) were evaluated by linear dependences. Dependence was not confirmed for c12,round and c12,board1 (r = 0.168), in contrast for c12,round and c12,log2 the dependence is statistically very significant (r = 0.634). The results of testing showed that the most suitable procedure for predicting quality of structural timber is the first step round timber – log2, the second step: log2 - board2. More exact results of the construction boards were obtained from log2 than from log1. The sound speed is used in the calculation of dynamic modulus of elasticity (Edyn). EN 408 mentions the possibility of using dynamic modulus of elasticity as an alternative method in predicting the quality of structural timber.

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Deficiencies in Silicone Impression for Crowns and Bridges

Revista de Chimie ◽

10.37358/rc.17.10.5876 ◽

2017 ◽

Vol 68 (10) ◽

pp. 2317-2319

Author(s):

Claudia Florina Andreescu ◽

Oana Botoaca ◽

Horia Mihail Barbu ◽

Doina Lucia Ghergic ◽

Anamaria Bechir ◽

...

Keyword(s):

Dental Practice ◽

Present Study Deal ◽

Dental Crowns ◽

Impression Materials ◽

Dental Practitioners ◽

Adequate Quality ◽

Dental Impression ◽

Single Crowns

There are many steps in fabrication of dental crowns and bridges at which an error can occur, and a technician can only fabricate a quality restoration if the impression itself is of adequate quality. All dental practitioners should have the ability to evaluate the quality of dental impression before sending to the laboratory. Elastomeric silicones (polysiloxane) are the most utilised impression materials in dental practice. The present study deal with the deficiencies of silicones dental impressions sent to commercial dental laboratories for fabrication of single crowns and bridges.

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Direct Metal Laser Sintering Strategies for Fabrication of Finer Resolution Cellular Structures

SSRN Electronic Journal ◽

10.2139/ssrn.3622647 ◽

2020 ◽

Author(s):

Fatemeh Hejripour ◽

Muhammad Abdus Salam ◽

Gary L. Bowlin ◽

Ebrahim Asadi

Keyword(s):

Laser Sintering ◽

Cellular Structures ◽

Direct Metal Laser Sintering

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Prediction of Maritime Pine Boards Modulus of Elasticity by Means of Sonic Testing on Green Timber

Applied Sciences ◽

10.3390/app11041748 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1748

Author(s):

Giovanna Concu

Keyword(s):

Modulus Of Elasticity ◽

Structural Timber ◽

Maritime Pine ◽

Manufacturing Costs ◽

Sonic Waves ◽

Wet Condition ◽

Structural Grade ◽

The Relationship ◽

Grade Yield

Timber buildings are experiencing a rapid diffusion due to their good performance and their sustainability; however, some steps of structural timber production process, such as drying, are energy-intensive and environmentally impactful, and many wood species are also affected by low yield. Therefore, it would be important to determine the quality of the green material, that is, in wet condition, before undergoing the most impactful and expensive production steps. This paper describes a research aimed at quantifying the variation of the dynamic modulus of elasticity MoEdyn, which is commonly used for structural timber mechanical grading, from wet to dry condition in Sardinian maritime pine boards to be used for the production of laminated timber, and to examine the relationship between wet and dry MoEdyn. The MoEdyn was determined from measurements of the velocity of sonic waves propagating through the boards. The results show that the dry MoEdyn can be estimated starting from boards sonic testing in the wet condition, so providing a basis for implementing Sardinian maritime pine pre-grading in order to obtain the reduction of manufacturing costs, the abatement of environmental impact, and the increase of structural grade yield.

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