scholarly journals A Comparison of the Compositional, Microstructural, and Mechanical Characteristics of Ni-Free and Conventional Stainless Steel Orthodontic Wires

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3424
Author(s):  
Daniela Brüngger ◽  
Theodoros Koutsoukis ◽  
Youssef S. Al Jabbari ◽  
Monika Hersberger-Zurfluh ◽  
Spiros Zinelis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Elemental Composition ◽  
Indentation Modulus ◽  
Limited Information ◽  
X Ray Diffraction ◽  
Orthodontic Wires ◽  
Promising Alternative ◽  
X Ray ◽  
Oriented Parallel

Ni-free orthodontic wires were introduced to mitigate concerns associated with the use of Ni-containing alloys in orthodontics. However, limited information is available on their properties and therefore, the aim of this study was to characterize the elemental composition, the microstructure, and the mechanical properties of Ni-free orthodontic wires and compare them with their stainless steel (SS) counterparts. Four Ni-free and four conventional SS wires were included in this study. All the wires were initially imaged with a Scanning Electron Microscopy (SEM) and their elemental compositions were determined by X-ray Energy Dispersive Spectroscopy (EDX). Then, their microstructure was assessed by X-ray Diffraction (XRD) and the indentation modulus, elastic index, Martens Hardness and Vickers Hardness by Instrumented Indentation Testing (IIT). All the wires demonstrated surface cracks and pores oriented parallel to their long axis. The elemental composition of Ni-free alloys showed an increased Mn and Cr content while both SS and Ni-free wires shared the same dominant austenite structure. In conclusion, despite the differences in elemental composition, Ni-free wires demonstrated a similar microstructure and comparable mechanical properties with their conventional SS counterparts and thus may be considered as a promising alternative for patients with Ni supersensitivity.

Microstructural Evolution during Tempering of 16Cr-5Ni Stainless Steel: Effects on Final Mechanical Properties

2013 ◽  
Vol 762 ◽  
pp. 176-182 ◽  
Author(s):  
Massimo De Sanctis ◽  
Renzo Valentini ◽  
Gianfranco Lovicu ◽  
Antonella Dimatteo ◽  
Randa Ishak ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Stainless Steel ◽  
Microstructural Evolution ◽  
Maximum Hardness ◽  
X Ray Diffraction ◽  
Structural Behaviour ◽  
X Ray ◽  
Transmission Electron ◽  
Normative Requirements ◽  
Double Tempering

In this work, the structural behaviour during tempering of two different heats of 16Cr-5Ni supermartensitic stainless steel has been studied by means of dilatometry, transmission electron microscopy and X-ray diffraction. A thermomechanical simulator (Gleeble 3800) has been also used to characterize the effects on final mechanical properties of different tempering temperatures in the range 600 °C to 700 °C and the influence of sub-zero cooling on industrial double tempering treatments. It has been found that the pre-existence of retained austenite in as-quenched conditions can induce significant differences in the microstructural evolution during tempering and on the final mechanical properties of industrial components, thus inducing problems in controlling final maximum hardness allowable by normative requirements.

scholarly journals The Influence of the Third Element on Nano-Mechanical Properties of Iron Borides FeB and Fe2B Formed in Fe-B-X (X = C, Cr, Mn, V, W, Mn + V) Alloys

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4155
Author(s):  
Ivana Kirkovska ◽  
Viera Homolová ◽  
Ivan Petryshynets ◽  
Tamás Csanádi
Keyword(s):  
Mechanical Properties ◽  
Indentation Size Effect ◽  
Microstructural Characterization ◽  
Indentation Hardness ◽  
Indentation Modulus ◽  
Instrumented Indentation ◽  
X Ray Diffraction ◽  
Alloying Element ◽  
X Ray

In this study, the influence of alloying elements on the mechanical properties of iron borides FeB and Fe2B formed in Fe-B-X (X = C, Cr, Mn, V, W, Mn + V) alloys were evaluated using instrumented indentation measurement. The microstructural characterization of the alloys was performed by means of X-ray diffraction and scanning electron microscope equipped with an energy dispersive X-ray analyzer. The fraction of the phases present in the alloys was determined either by the lever rule or by image analysis. The hardest and stiffest FeB formed in Fe-B-X (X = C, Cr, Mn) alloys was observed in the Fe-B-Cr alloys, where indentation hardness of HIT = 26.9 ± 1.4 GPa and indentation modulus of EIT = 486 ± 22 GPa were determined. The highest hardness of Fe2B was determined in the presence of tungsten as an alloying element, HIT = 20.8 ± 0.9 GPa. The lowest indentation hardness is measured in manganese alloyed FeB and Fe2B. In both FeB and Fe2B, an indentation size effect was observed, showing a decrease of hardness with increasing indentation depth.

Assessment of Fire Damage to 321 Stainless Steel Equipment in a Chemical Unit

2007 ◽  
Vol 345-346 ◽  
pp. 1373-1376
Author(s):  
Wei Zhang ◽  
Zeng Liang Gao ◽  
Kangda Zhang ◽  
Zheng Fang ◽  
Xiao Yan Lu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Stainless Steel ◽  
External Surface ◽  
Chemical Compositions ◽  
Fire Damage ◽  
X Ray Diffraction ◽  
X Ray ◽  
Steel Equipment ◽  
Scanning Electron

In the present work, the mechanical properties of 321 stainless steel pressure equipments exposed to an accident fire in a chemical unit were investigated. The performance and microstructure of this material were described by chemical compositions analysis, tensile test, scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The experiment results showed that the mechanical properties of the material were degraded. The grains on the external surface of the fracture became coarse. These results indicated that serious damage to 321 stainless steel had been induced by extreme heat of the fire and this pressure vessel could not be used anymore.

Study of Microstructure and Mechanical Properties of an Ankle Prosthesis Removing

2015 ◽  
Vol 1766 ◽  
pp. 19-25
Author(s):  
J. G. Flores Becerra ◽  
N. López Perrusquia ◽  
M. A. Doñu Ruiz ◽  
A. López Perrusquia ◽  
J.V. Cortes Suarez
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Stainless Steel ◽  
Microstructural Change ◽  
Prosthetic Material ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ankle Prosthesis ◽  
Corrosion Pits ◽  
Scanning Electron

ABSTRACTThis work studies the change microstructural and mechanical properties of an ankle prosthetic material 316LVM stainless steel, retired from a 36 year old patient. The medical grade 316LVM stainless steel was characterized by scanning electron microscopy (SEM), optical microscopy (OM), X-ray diffraction (XRD), hardness Rockwell C (HRC) and nanoindentation tests. The results showed that the ankle prosthesis has different microstructural change along the implant and presence of corrosion pits with inclusions, the mechanical properties like modulus elasticity and hardness decrease.

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

2019 ◽  
Vol 107 (2) ◽  
pp. 207 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Veronika Kadlecová ◽  
Jiří Čapek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Young’S Modulus ◽  
Milling Time ◽  
Young's Modulus ◽  
Element Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles ◽  
Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

scholarly journals Enhancement of Chloroprene/Natural/Butadiene Rubber Nanocomposite Properties Using Organoclays and Their Combination with Carbon Black as Fillers

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1085
Author(s):  
Patricia Castaño-Rivera ◽  
Isabel Calle-Holguín ◽  
Johanna Castaño ◽  
Gustavo Cabrera-Barjas ◽  
Karen Galvez-Garrido ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Carbon Black ◽  
High Performance ◽  
Rubber Matrix ◽  
Butadiene Rubber ◽  
X Ray Diffraction ◽  
X Ray ◽  
Rubber Blends ◽  
Ft Ir ◽  
Chloroprene Rubber

Organoclay nanoparticles (Cloisite® C10A, Cloisite® C15) and their combination with carbon black (N330) were studied as fillers in chloroprene/natural/butadiene rubber blends to prepare nanocomposites. The effect of filler type and load on the physical mechanical properties of nanocomposites was determined and correlated with its structure, compatibility and cure properties using Fourier Transformed Infrared (FT-IR), X-ray Diffraction (XRD), Thermogravimetric Analysis (TGA) and rheometric analysis. Physical mechanical properties were improved by organoclays at 5–7 phr. Nanocomposites with organoclays exhibited a remarkable increase up to 46% in abrasion resistance. The improvement in properties was attributed to good organoclay dispersion in the rubber matrix and to the compatibility between them and the chloroprene rubber. Carbon black at a 40 phr load was not the optimal concentration to interact with organoclays. The present study confirmed that organoclays can be a reinforcing filler for high performance applications in rubber nanocomposites.

scholarly journals The Potential for Natural Stones from Northeastern Brazil to Be Used in Civil Construction

Minerals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 440
Author(s):  
Fabiana Pereira da Costa ◽  
Jucielle Veras Fernandes ◽  
Luiz Ronaldo Lisboa de Melo ◽  
Alisson Mendes Rodrigues ◽  
Romualdo Rodrigues Menezes ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Chemical Resistance ◽  
Mechanical Analysis ◽  
Northeastern Brazil ◽  
X Ray Diffraction ◽  
X Ray ◽  
Chemical Agents ◽  
Natural Stones

Natural stones (limestones, granites, and marble) from mines located in northeastern Brazil were investigated to discover their potential for use in civil construction. The natural stones were characterized by chemical analysis, X-ray diffraction, differential thermal analysis, and optical microscopy. The physical-mechanical properties (apparent density, porosity, water absorption, compressive and flexural strength, impact, and abrasion) and chemical resistance properties were also evaluated. The results of the physical-mechanical analysis indicated that the natural stones investigated have the potential to be used in different environments (interior, exterior), taking into account factors such as people’s circulation and exposure to chemical agents.

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