Characterization of the Effect of Cr Additions to TiAl-Base Alloys

1990 ◽  
Vol 186 ◽  
Author(s):  
Shyh-Chin Huang ◽  
Ernest L. Hall
Keyword(s):  
Mechanical Behavior ◽  
Phase Stability ◽  
Single Phase ◽  
Site Occupancy ◽  
Volume Ratio ◽  
Deformation Mode ◽  
Twin Formation

AbstractTernary TiAl-base alloys containing Cr have been studied, using rapidsolidification processed materials. The mechanical behavior has been characterized and related to other results on microstructure, site occupancy, phase stability, and deformation mode. It was found that Cr additions enhance the plasticity of duplex γ+a2 alloys, but not single-phase alloys. The ductilization effect of Cr is partially due to its ability to occupy Al lattice sites and modify the Ti-Al bond. It is also partially due to its ability to promote twin formation, by modifying the Al partitioning and therefore the a2/γ volume ratio in transformed regions.

Mechanical Behavior of Titanium Alloys under Different Conditions of Loading

2018 ◽  
Vol 941 ◽  
pp. 839-844 ◽  
Author(s):  
Pavlo E. Markovsky
Keyword(s):  
Phase Composition ◽  
Mechanical Behavior ◽  
Deformation Rate ◽  
Single Phase ◽  
Deformation Mode ◽  
Tensile Tests ◽  
Deformation Energy ◽  
Two Phase ◽  
The Matrix ◽  
Size And Morphology

Taking three titanium commercial alloys: commercial purity titanium (c.p.Ti, single-phase α), Ti64 (Ti-6(wt.%)Al-4V, two-phase α+β) and TIMETAL-LCB (Ti-1.5Al-4.5Fe-6.8Mo, both two-phase α+β and single-phase β) as program materials, the influence of phase composition, microstructure and deformation rate (VD, varied from 10-4 to 101 s-1), and deformation mode (compression and 3-point flexure) on the mechanical behavior was studied and compared with data earlier obtained during tensile tests. The size of the matrix phase (alpha- or beta-grains) size and morphology of α+β intragranular mixture were varied using different treatments. Deformation Energy (UD) was used for analysis of the mechanical behavior of the materials tested. It was found that the UD dependencies on deformation rate are different for different methods of loading and are determined by a combination of the phase composition, dispersion, and morphology of the phase constituents. More ductile and less dependent on VD behavior showed c.p.Ti and Ti64 with globular microstructure on all three testing modes, while other materials had some negative features depending on the certain test conditions. Details of mechanical behavior, peculiarities of pores and cracks nucleation causing in final fracture are discussed basing on the results of detailed microstructure study of tested specimens.

scholarly journals Fabrication and Characterization of Quinary High Entropy-Ultra-High Temperature Diborides

Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 108-120
Author(s):  
Simone Barbarossa ◽  
Roberto Orrù ◽  
Valeria Cannillo ◽  
Antonio Iacomini ◽  
Sebastiano Garroni ◽  
...  
Keyword(s):  
High Temperature ◽  
Single Phase ◽  
Nominal Composition ◽  
High Entropy ◽  
Chemical Complexity ◽  
Alternative Processing ◽  
Plasma Sintering ◽  
High Temperature Synthesis ◽  
Spark Plasma

Due to their inherent chemical complexity and their refractory nature, the obtainment of highly dense and single-phase high entropy (HE) diborides represents a very hard target to achieve. In this framework, homogeneous (Hf0.2Nb0.2Ta0.2Mo0.2Ti0.2)B2, (Hf0.2Zr0.2Ta0.2Mo0.2Ti0.2)B2, and (Hf0.2Zr0.2Nb0.2Mo0.2Ti0.2)B2 ceramics with high relative densities (97.4, 96.5, and 98.2%, respectively) were successfully produced by spark plasma sintering (SPS) using powders prepared by self-propagating high-temperature synthesis (SHS). Although the latter technique did not lead to the complete conversion of initial precursors into the prescribed HE phases, such a goal was fully reached after SPS (1950 °C/20 min/20 MPa). The three HE products showed similar and, in some cases, even better mechanical properties compared to ceramics with the same nominal composition attained using alternative processing methods. Superior Vickers hardness and elastic modulus values were found for the (Hf0.2Nb0.2Ta0.2Mo0.2Ti0.2)B2 and the (Hf0.2Zr0.2Ta0.2Mo0.2Ti0.2)B2 systems, i.e., 28.1 GPa/538.5 GPa and 28.08 GPa/498.1 GPa, respectively, in spite of the correspondingly higher residual porosities (1.2 and 2.2 vol.%, respectively). In contrast, the third ceramic, not containing tantalum, displayed lower values of these two properties (25.1 GPa/404.5 GPa). However, the corresponding fracture toughness (8.84 MPa m1/2) was relatively higher. This fact can be likely ascribed to the smaller residual porosity (0.3 vol.%) of the sintered material.

scholarly journals Ultrafiltration Method for Plasma Protein Binding Studies and Its Limitations

Processes ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 382
Author(s):  
Camelia-Maria Toma ◽  
Silvia Imre ◽  
Camil-Eugen Vari ◽  
Daniela-Lucia Muntean ◽  
Amelia Tero-Vescan
Keyword(s):  
Protein Binding ◽  
Plasma Protein Binding ◽  
Plasma Protein ◽  
Specific Binding ◽  
Critical Role ◽  
Volume Ratio ◽  
Binding Studies ◽  
Experimental Conditions ◽  
Key Aspects

Plasma protein binding plays a critical role in drug therapy, being a key part in the characterization of any compound. Among other methods, this process is largely studied by ultrafiltration based on its advantages. However, the method also has some limitations that could negatively influence the experimental results. The aim of this study was to underline key aspects regarding the limitations of the ultrafiltration method, and the potential ways to overcome them. The main limitations are given by the non-specific binding of the substances, the effect of the volume ratio obtained, and the need of a rigorous control of the experimental conditions, especially pH and temperature. This review presents a variety of methods that can hypothetically reduce the limitations, and concludes that ultrafiltration remains a reliable method for the study of protein binding. However, the methodology of the study should be carefully chosen.

In Situ Characterization of the Mechanical Behavior of Gecko's Spatulae by Atomic Force Microscopy

2013 ◽  
Vol 22 ◽  
pp. 85-93
Author(s):  
Shuang Yi Liu ◽  
Min Min Tang ◽  
Ai Kah Soh ◽  
Liang Hong
Keyword(s):  
Mechanical Behavior ◽  
Hierarchical Level ◽  
Intrinsic Properties ◽  
In Situ Characterization ◽  
Force Microscopy ◽  
Atomic Force ◽  
Theoretical Predictions ◽  
Multi Mode

In-situ characterization of the mechanical behavior of geckos spatula has been carried out in detail using multi-mode AFM system. Combining successful application of a novel AFM mode, i.e. Harmonix microscopy, the more detail elastic properties of spatula is brought to light. The results obtained show the variation of the mechanical properties on the hierarchical level of a seta, even for the different locations, pad and stalk of the spatula. A model, which has been validated using the existing experimental data and phenomena as well as theoretical predictions for geckos adhesion, crawling and self-cleaning of spatulae, is proposed in this paper. Through contrast of adhesive and craw ability of the gecko on the surfaces with different surface roughness, and measurement of the surface adhesive behaviors of Teflon, the most effective adhesion of the gecko is more dependent on the intrinsic properties of the surface which is adhered.

Characterization of CuSbSe2 crystallites synthesized using a hot injection method

RSC Advances ◽  
2016 ◽  
Vol 6 (101) ◽  
pp. 99297-99305 ◽  
Author(s):  
Hsing-I. Hsiang ◽  
Chang-Ting Yang ◽  
Jui-Huan Tu
Keyword(s):  
Single Phase ◽  
Triethylene Glycol ◽  
Reducing Agent ◽  
Injection Method ◽  
Hot Injection ◽  
Low Toxic

In this study, a novel and facile hot injection method for the synthesis of single phase CuSbSe2 crystallites was developed by using low toxic triethylene glycol as both the solvent and reducing agent and triethylenetetramine as co-reducing agent.

Sign in / Sign up

Export Citation Format

Share Document