Young's modulus of heat-treated carbons: A theory for nongraphitizing carbons

Carbon ◽  
1993 ◽  
Vol 31 (2) ◽  
pp. 333-339 ◽  
Author(s):  
F.G. Emmerich ◽  
C.A. Luengo
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Heat Treated

Development of Ti-12Mo-8Nb Alloy for Biomedical Application

2017 ◽  
Vol 899 ◽  
pp. 191-194
Author(s):  
Sinara Borborema Gabriel ◽  
Jessica Peixoto da Silva Kassya ◽  
Caroline Miranda Jacinto ◽  
Leizy Pâmela Oliveira dos Santos ◽  
Carlos Angelo Nunes ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Biomedical Application ◽  
Young's Modulus ◽  
High Vacuum ◽  
High Strength ◽  
Microstructural Characterization ◽  
Β Phase ◽  
Beta Titanium ◽  
Heat Treated ◽  
Alloy Heat

Several beta titanium alloys were developed for biomedical applications due to the combination of low elasticity modulus, high strength, fatigue resistance and good ductility with excellent corrosion resistance. In this regard, a new metastable beta titanium Ti-12Mo-8Nb alloy was developed, as an alternative for the traditional Ti-6Al-4V alloy, with the substitution of vanadium and aluminum for molybdenum and niobium. The objective of this work was to present the microstructural characterization and mechanical properties of the Ti-12Mo-8Nb alloy, heat treated for 1h at 950oC under high vacuum and then water quenched. The microstructure of the alloy was characterized by X-ray diffraction and optical microscopy. Vickers microhardness and nanoindentation were performed for determination of hardness, Young’s modulus and the ratio of hardness to Young’s modulus. The Ti-12Mo-8Nb microstructure consisted of β phase and the values obtained for the ratio of hardness to Young’s modulus were higher than the Ti-6Al-4V alloy.

Temperature dependences of the Young's modulus and internal friction of heat-treated silicon

1970 ◽  
Vol 13 (3) ◽  
pp. 366-370
Author(s):  
L. N. Aleksandrov ◽  
M. I. Zotov ◽  
F. L. �del'man
Keyword(s):  
Internal Friction ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Heat Treated ◽  
Temperature Dependences

scholarly journals A 3D-Printed Ultra-Low Young’s Modulus β-Ti Alloy for Biomedical Applications

Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2792 ◽  
Author(s):  
Massimo Pellizzari ◽  
Alireza Jam ◽  
Matilde Tschon ◽  
Milena Fini ◽  
Carlo Lora ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Biomedical Applications ◽  
Young's Modulus ◽  
Total Elongation ◽  
Potential Candidate ◽  
Β Phase ◽  
Grade 5 ◽  
Heat Treated ◽  
Columnar Grains ◽  
3D Printed

The metastable β-Ti21S alloy is evaluated as a potential candidate for biomedical parts. Near fully dense (99.75 ± 0.02%) samples are additively manufactured (that is, 3D-printed) by laser powder-bed fusion (L-PBF). In the as-built condition, the material consists of metastable β-phase only, with columnar grains oriented along the building direction. The material exhibits an extremely low Young’s modulus (52 ± 0.3 GPa), which was never reported for this type of alloy. The combination of good mechanical strength (σy0.2 = 709 ± 6 MPa, ultimate tensile strength (UTS) = 831 ± 3 MPa) and high total elongation during tensile test (21% ± 1.2%) in the as-built state, that is, without any heat treatment, is close to that of the wrought alloy and comparable to that of heat treated Ti grade 5. The good biocompatibility attested by cytotoxicity tests confirms its great suitability for biomedical applications.

scholarly journals A Study of the Effects of Al, Cr, Hf, and Ti Additions on the Microstructure and Oxidation of Nb-24Ti-18Si Silicide Based Alloys

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1579 ◽  
Author(s):  
Jack Nelson ◽  
Mohammad Ghadyani ◽  
Claire Utton ◽  
Panos Tsakiropoulos
Keyword(s):  
Solid Solution ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Isothermal Oxidation ◽  
Bulk Alloy ◽  
Simultaneous Addition ◽  
Hardening Effect ◽  
Heat Treated ◽  
Alloy Oxidation ◽  
Negative Effect

In Nb-silicide based alloys Al, Cr, Hf, and Ti additions are crucial for achieving balance of properties. It is not known how the simultaneous addition of Hf with Al and Ti, or Hf with Al, Cr, and Ti affects macrosegregation, and how the alloying affects hardness, Young’s modulus and bulk alloy oxidation, and contamination of the solid solution Nbss and the Nb5Si3 compound by oxygen. Two alloys with nominal compositions (at.%) Nb-24Ti-18Si-5Al-5Hf (alloy NbSiTiHf-5Al) and Nb-24Ti-18Si-5Al-5Cr-5Hf (alloy NbSiTiHf-5Al-5Cr) were studied in the as-cast and heat-treated conditions and after isothermal oxidation at 800 and 1200 °C and were compared with similar alloys without Hf. In both alloys there was macrosegregation of Si and Ti, which was more severe in NbSiTiHf-5Al. Both alloys formed Nbss+βNb5Si3 eutectic. The Nbss was stable and its Al and Cr concentrations increased with increasing Ti concentration. In both conditions the βNb5Si3 was observed in the alloys NbSiTiHf-5Al and NbSiTiHf-5Al-5Cr, and the γNb5Si3 only in the alloy NbSiTiHf-5Al. In both heat-treated alloys, separate Hf-rich Nb5Si3 grains were formed. The Si and Al concentrations in Nb5Si3 respectively decreased and increased with increasing Ti concentration. Al and Cr had a stronger hardening effect in the Nbss than Al, Cr, and Hf. Al, Cr, and Ti had a stronger negative effect on the Young’s modulus of the Nbss compared with Al, Cr, Hf, and Ti. When Nb was substituted by Ti, Cr, and Hf, and Si by Al in the βNb5Si3, the Young’s modulus was reduced compared with the unalloyed silicide. At 800 °C both alloys did not exhibit catastrophic pest-oxidation after 100 h. The Nbss and Nb5Si3 were contaminated by oxygen in both alloys, the former more severely. At 1200 °C the scales spalled-off, more severely in the alloy NbSiTiHf-5Al, where substrate that was heavily contaminated by oxygen below the scale also spalled-off. In both alloys the contamination of Nb5Si3 and Nbss by oxygen was more severe compared with 800 °C, but the silicides were not contaminated by oxygen in their bulk. The Nbss was not contaminated by oxygen only in the bulk of the alloy NbSiTiHf-5Al-5Cr.

Effects of the Heat Treatment on the Mechanical Properties of a Novel Thermotropic Liquid-Crystalline Polymer Fiber

2011 ◽  
Vol 181-182 ◽  
pp. 63-66
Author(s):  
Wei Biao Zhu ◽  
Hai Xiao Gan ◽  
Yuan Yuan Zhuang ◽  
Wei Min Qin ◽  
Yan Ping Wang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Young’S Modulus ◽  
Melt Spinning ◽  
Liquid Crystalline ◽  
Treatment Time ◽  
Breaking Strength ◽  
Young's Modulus ◽  
Crystalline Polymer ◽  
Treatment Temperature ◽  
Heat Treated

Thermotropic liquid-crystalline polymers (TLCPs) have aroused wide public concern which is attributed to their high strength, stiffness, chemical resistance and perfect dimensional stability as high-performance engineering materials. Vectran heat treated after melt spinning is a representative commercial aromatic copolyester fiber. In this study, a novel TLCP melt-polymerized with 4,4’-diphenyloxide dicarboxylic acid (DODA), 4-acetoxybenzoic acid (ABA), hydroquinone diactate (HQA), 2,6-naphthalene dicarboxylic (NDA) and terephthalic acid (TA) were melt spun into fibers and heat treated to enhance the breaking strength and Young’s modulus. Intermolecular mechanical elements slipped between 120-130 °C and crystallization or the conformational rotations occurred along the extended polymer chain. For this new TLCP fiber, the optimal heat treatment temperature was 260 °C and the suitable heat-treatment time was over 48 hours. The breaking strength, Young’s modulus and breaking elongation of the as-spun fiber were improved from 1.58GPa, 45.21GPa and 1.97% to 3.20GPa, 133.44GPa and 2.42% respectively after heat treatment.

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.

Degradation of Rocks, Through Cracking Caused by Differential Thermal Expansion, in Relation to Nuclear Waste Repositories

1981 ◽  
Vol 6 ◽  
Author(s):  
J.R. Mclaren ◽  
R.W. Davidge ◽  
I. Titchell ◽  
K. Sincock ◽  
A. Bromley
Keyword(s):  
Thermal Expansion ◽  
Grain Boundary ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Crack Density ◽  
Granitic Rocks ◽  
Multiphase Materials ◽  
Thermal Expansion Behaviour ◽  
Waste Repositories ◽  
Expansion Behaviour

ABSTRACTHeating to temperatures up to 500°C, gives a reduction in Young's modulus and increase in permeability of granitic rocks and it is likely that a major reason is grain boundary cracking. The cracking of grain boundary facets in polycrystalline multiphase materials showing anisotropic thermal expansion behaviour is controlled by several microstructural factors in addition to the intrinsic thermal and elastic properties. Of specific interest are the relative orientations of the two grains meeting at the facet, and the size of the facet; these factors thus introduce two statistical aspects to the problem and these are introduced to give quantitative data on crack density versus temperature. The theory is compared with experimental measurements of Young's modulus and permeability for various rocks as a function of temperature. There is good qualitative agreement, and the additional (mainly microstructural) data required for a quantitative comparison are defined.

Is it necessary to calculate Young’s modulus in AFM nanoindentation experiments regarding biological samples?

2020 ◽  
Vol 12 ◽  
Author(s):  
S.V. Kontomaris ◽  
A. Malamou ◽  
A. Stylianou
Keyword(s):  
Young’S Modulus ◽  
Biological Samples ◽  
Young's Modulus ◽  
Reference Sample ◽  
Nonlinear Behavior ◽  
Accurate Method ◽  
Accurate Solution ◽  
Hertz Model ◽  
Work Done

Background: The determination of the mechanical properties of biological samples using Atomic Force Microscopy (AFM) at the nanoscale is usually performed using basic models arising from the contact mechanics theory. In particular, the Hertz model is the most frequently used theoretical tool for data processing. However, the Hertz model requires several assumptions such as homogeneous and isotropic samples and indenters with perfectly spherical or conical shapes. As it is widely known, none of these requirements are 100 % fulfilled for the case of indentation experiments at the nanoscale. As a result, significant errors arise in the Young’s modulus calculation. At the same time, an analytical model that could account complexities of soft biomaterials, such as nonlinear behavior, anisotropy, and heterogeneity, may be far-reaching. In addition, this hypothetical model would be ‘too difficult’ to be applied in real clinical activities since it would require very heavy workload and highly specialized personnel. Objective: In this paper a simple solution is provided to the aforementioned dead-end. A new approach is introduced in order to provide a simple and accurate method for the mechanical characterization at the nanoscale. Method: The ratio of the work done by the indenter on the sample of interest to the work done by the indenter on a reference sample is introduced as a new physical quantity that does not require homogeneous, isotropic samples or perfect indenters. Results: The proposed approach, not only provides an accurate solution from a physical perspective but also a simpler solution which does not require activities such as the determination of the cantilever’s spring constant and the dimensions of the AFM tip. Conclusion: The proposed, by this opinion paper, solution aims to provide a significant opportunity to overcome the existing limitations provided by Hertzian mechanics and apply AFM techniques in real clinical activities.

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