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Showing 1 to 18 of 18 for “"Ti-Nb"”.
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Diffusion of titanium and niobium in b.c.c. Ti-Nb alloys
The diffusion coefficients for titanium and niobium radioactive tracers were simultaneously measured in Ti, Ti94.6, Ti80.4, Nb19.6 and Ti64.3Nb35.7 over the temperature range from 9S0°C to 1511°C using 643 3S standard lathe sectioning techniques. The samples were initially heat treated by annealing …
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Understanding the formation and influence of the omega phase in metastable beta Ti-Nb based alloys
Metastable β-Ti alloys have potential applications ranging from low modulus biomedical alloys to vibration damping in aerospace. This is, in part, due to the ability of certain compositions to undergo a stress induced transformation to the martensitic α″ phase, enabling superelasticity. However, …
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An investigation into the influence of microstructural condition on the superelastic behaviour in Ti-Nb-based alloys.
Ti-Nb based alloys show superelastic and shape memory properties over a wide range of temperatures, making them attractive for industrial applications. However, within the literature there are significant variations in the reported martensite start temperatures that have not been rationalised. To …
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The Effect of Equal Channel Angular Extrusion (ECAE) and Boron Additions on the Mechanical Properties of a Biomedical Ti-Nb-Zr-Ta (TNZT) Alloy
New metastable-beta type titanium alloys based on the biocompatible elements Ti-Nb-Zr-Ta: TNZT) have been developed to address the shortcomings: e.g. incomplete biocompatibility, high modulus, etc.) of the traditionally used materials in joint replacement prostheses. Equal channel angular …
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ΔΟΜΙΚΟΙ ΜΕΤΑΣΧΗΜΑΤΙΣΜΟΙ ΚΑΤΑ ΤΗΝ ΑΝΟΠΤΗΣΗ ΑΝΟΞΕΙΔΩΤΩΝ ΦΕΡΡΙΤΙΚΩΝ ΧΑΛΥΒΩΝ ΚΑΙ Η ΕΠΙΔΡΑΣΗ ΤΟΥΣ ΣΤΗ ΣΥΜΠΕΡΙΦΟΡΑ ΚΑΤΑ ΤΗ ΘΡΑΥΣΗ ΚΑΙ ΚΑΤΑ ΤΗΝ ΟΞΕΙΔΩΣΗ ΥΨΗΛΗΣ ΘΕΡΜΟΚΡΑΣΙΑΣ
THE STRUCTURAL TRANSFORMATIONS OF CAST FERRITIC STAINLESS STEELS WITH 28-30% CR, 0.3-0.35% C AND ZR, TI, NB, NI ADDITIONS DURING LONG PERIOD ANNEALING AT 660 C, WERE STUDIED, BY MEANS OF OPTICAL AND ELECTRON MICROSCOPY, X-RAY DIFFRACTIONAND FLUORESCENCE, IMAGE ANALYSIS AND MOSSBAUER SPECTROSCOPY. …
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Development of novel redox stable anode materials and their suitability for use in intermediate temperature solid oxide fuel cells
Due to the material benefits in the reduction of the operating temperatures of SOFCs, development of novel electrolyte and electrode materials is deemed to be essential for SOFC performance optimisation at intermediate temperatures. Iron-based perovskites were previously overlooked as anode …
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Selective laser melting of Ti-35NB alloy: Processing, microstructure and properties
The initiative of a sustainable material system needs to lower the environmental and economic impact of production processes and adopt new ways of synthesizing and re-using materials. Even though the current conventional manufacturing processes, such as powder metallurgy, casting, forging, and …
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Bauschinger effect in Nb and V microalloyed line pipe steels
Chemical composition of structural steels with a ferrite-pearlite microstructure has been developing towards decreasing carbon content, to increase weldability, with increased microalloying element content, to provide grain refinement, solid solution and precipitation strengthening. During the UOE …
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Development of bimodal grain structures and their effect on toughness in HSLA steel
To understand the formation of bimodal ferrite grain structures (i.e. mixed coarse + fine grain sizes) in TMCR HSLA steel plates, as-continuously cast HSLA steel slabs with varying microalloying additions (Ti, Nb and V) were reheated to temperatures in the range 1000-1300 °C and deformed at 1110 °C …
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Behaviour of Critical Metals During Smelting of Copper Concentrates from Olympic Dam Plant, South Australia
This thesis provides a comprehensive characterisation of slags produced during direct-to-blister copper smelting at Olympic Dam, South Australia. It aims at measuring and interpreting the content and behaviour of selected critical elements in slags,: rare earths elements (REE), Co, Ni, Ti, Nb, and …
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Development of Precision 3D-Printed Medical Implants
This research investigated the cellular efficacies of combining biocompatibility and antibacterial properties in biomedical materials. The osteogenic response of both osteoblast and osteocyte cells and the bacteria S. aureus adhesion on a newly developed titanium alloy Ti-12Nb-12Zr-12Sn alloy …
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Strip with gradient properties by annealing in reactive atmospheres
Interstitial Free (IF) steels have excellent deep drawing capabilities and non-ageing properties. These steel grades still have some disadvantages such as a generally weak mechanical strength and high reactivity in the grain boundaries during galvannealing, which produces brittle …
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Vertically Aligned Nanocomposite Thin Films for Micro-Battery and Nanoionic Applications
… are a necessity for powering the next generation of flexible electronics, internet of things and MedTech devices. In theory, significant improvements in the capacity, current and power densities of micro-batteries would result if 3-dimensional architectures were used, as they have both …
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Materials For Energy: Complex Oxides And Nitrides For New Polymer Electrolyte Membrane Fuel Cell Catalysts And Supports
… are required for large-scale commercialization of PEMFCS, and must be stable in low pH (1-2) and up to +1.5 V (vs. SHE). The material also needs to be porous and conducting (at least 0.1 S cm-1). Furthermore, the catalyst support should also be capable of strongly binding Pt or Pt-based …
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A Mechanistic Understanding of the β to α′′ Transformation in Superelastic Ti-24Nb-4Zr-8Sn (wt%)
Metastable β titanium alloys have potential for application in vibration damping systems, due to their wide mechanical hysteresis and large recoverable strains, arising from a re- versible martensitic transformation between a parent bcc β phase and an orthorhombic α′′ martensite. Of these alloys, …
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Design, microstructure and mechanical properties of new Ti-based alloys
… molecular orbital method three new series of TixFe- yTa, Ti-Fe-xNb and Ti-Nb-xFe alloys are designed for the first time. The alloys are then produced by cold crucible levitation technique. The influence of Ta, Fe and Nb contents on the phase transformation, β phase stability and …
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Critical stresses for twinning, slip and transformation in shape memory alloys: modeling and experiments
There are four important parameters-(i) transformation stress (ii) twinning stress (iii) austenite slip stress and (iv) martensite slip stress that govern shape memory and superelastic behavior in shape memory alloys (SMAs). However, it is a tremendous experimental effort to determine these …