1
|
Garnier M, Lesniewska E, Optasanu V, Guelorget B, Berger P, Lavisse L, François M, Custovic I, Pocholle N, Bourillot E. Submicronic-Scale Mechanochemical Characterization of Oxygen-Enriched Materials. Nanomaterials (Basel) 2024; 14:628. [PMID: 38607162 PMCID: PMC11013239 DOI: 10.3390/nano14070628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 03/29/2024] [Accepted: 04/01/2024] [Indexed: 04/13/2024]
Abstract
Conventional techniques that measure the concentration of light elements in metallic materials lack high-resolution performance due to their intrinsic limitation of sensitivity. In that context, scanning microwave microscopy has the potential to significantly enhance the quantification of element distribution due to its ability to perform a tomographic investigation of the sample. Scanning microwave microscopy associates the local electromagnetic measurement and the nanoscale resolution of an atomic force microscope. This technique allows the simultaneous characterization of oxygen concentration as well as local mechanical properties by microwave phase shift and amplitude signal, respectively. The technique was calibrated by comparison with nuclear reaction analysis and nanoindentation measurement. We demonstrated the reliability of the scanning microwave technique by studying thin oxygen-enriched layers on a Ti-6Al-4V alloy. This innovative approach opens novel possibilities for the indirect quantification of light chemical element diffusion in metallic materials. This technique is applicable to the control and optimization of industrial processes.
Collapse
Affiliation(s)
- Marie Garnier
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Eric Lesniewska
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Virgil Optasanu
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Bruno Guelorget
- Laboratory of Mechanical & Material Engineering (UR LASMIS), University of Technology Troyes, 10300 Troyes, France; (B.G.)
| | - Pascal Berger
- Laboratory Nanoscience and Innovation for Materials, Biomedecine and Energy (NIMBE), UMR 3685 CEA-CNRS, University of Paris-Saclay, 91191 Gif-sur-Yvette, France
| | - Luc Lavisse
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Manuel François
- Laboratory of Mechanical & Material Engineering (UR LASMIS), University of Technology Troyes, 10300 Troyes, France; (B.G.)
| | - Irma Custovic
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Nicolas Pocholle
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| | - Eric Bourillot
- Laboratory Interdisciplinaire Carnot de Bourgogne (ICB), UMR 6303 CNRS, University of Bourgogne, 21000 Dijon, France
| |
Collapse
|
2
|
Moayedee Y, Nikzad L, Majidian H. Exploration into the microstructural, mechanical, and biological characteristics of the functionally graded 3Y-TZP/Ti6Al4V system as a potential material for dental implants. J Mech Behav Biomed Mater 2024; 151:106380. [PMID: 38215657 DOI: 10.1016/j.jmbbm.2024.106380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 01/02/2024] [Accepted: 01/03/2024] [Indexed: 01/14/2024]
Abstract
This study investigated the mechanical, microstructural, and biological properties of 3Y-TZP/Ti6Al4V functionally graded material (FGM) fabricated by the spark plasma sintering (SPS) method. For this purpose, 11 layers of 100-x vol% Ti6Al4V/x vol% Yttria stabilized zirconia (YSZ) (x = 0 to 100) were sintered at 1450 °C and a pressure of 30 MPa for 8 min. To investigate the properties of each layer in more detail, 11 batches of 100-x vol% (Ti6Al4V)/x vol% YSZ (x = 0 to 100) composites were sintered separately with the same sintering conditions mentioned for the FGM sample. Phase identification of the FGM sample showed the formation of Ti3O, c-ZrO2, and Zr3O phases as by-products. A schematic model was proposed for the formation of the mentioned phases with the aid of thermodynamic calculations. The formation of these phases was confirmed by microstructural and elemental tests. The results of the relative density of the samples showed that these values were obtained for each layer above 99%. The microhardness of 590 ± 18 Vickers was obtained for Ti6Al4V; by increasing the amount of 3Y-TZP, this value reached 1510 ± 24 Vickers for the YSZ sample. The fracture toughness value for Ti6Al4V was 39.2 ± 2 MPa m0.5, which was significantly reduced to 4.84 ± 1 MPa m0.5 by adding 10 vol% YSZ. After that, with the further increase of YSZ, this value increased slowly. A similar trend was observed for the bending strength of the samples. By increasing 3Y-TZP from 0 to 30 vol%, the bending strength was decreased from 1556 ± 32 to 272 ± 62 MPa. By further increasing the amount of 3Y-TZP from 30 to 100 vol%, an increase in the bending strength was observed in the samples, which reached 1180 ± 71 MPa for the YSZ sample. The FGM sample showed a brittle fracture despite a metal layer, but a higher bending strength (982 ± 44 MPa) was obtained for this structure than the composite samples. The biological results show that increasing YSZ content leads to a decrease in antimicrobial activity. Additionally, all samples demonstrated high biocompatibility based on MTT cytotoxicity tests after 1 and 7 days of culture.
Collapse
Affiliation(s)
- Yeganeh Moayedee
- Department of Ceramics, Materials and Energy Research Center, Karaj, Iran
| | - Leila Nikzad
- Department of Ceramics, Materials and Energy Research Center, Karaj, Iran.
| | - Houdsa Majidian
- Department of Ceramics, Materials and Energy Research Center, Karaj, Iran
| |
Collapse
|
3
|
Mohamed LZ, Abd Elmomen SS, El‐Hadad S. Investigating the thermal oxidation behavior of Ti–6Al–7Nb alloy in dry air. Materials & Corrosion 2022; 73:1553-1562. [DOI: 10.1002/maco.202112957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Accepted: 05/04/2022] [Indexed: 09/02/2023]
Abstract
AbstractThe thermal oxidation behavior of a forged Ti–6Al–7Nb (Ti67) alloy was investigated in dry air conditions. The alloy specimens were oxidized for 50 h at different temperatures (650°C, 750°C, and 850°C) and the oxidation kinetics were analyzed. The microstructure of Ti67 after oxidation and the different phases and compounds were identified. A parabolic equation based on weight gain was used to define the oxidation rate. The parabolic rate constant increased from 1.10 × 10−8 at 650°C to 2.10 × 10−8 and 1.53 × 10−7 g2/(cm4·h) at 750°C and 850°C, respectively. At 650°C, the oxidation behavior resumed the parabolic behavior until 40 h, a breakaway phenomenon. At 750°C, a linear behavior was observed in the periods of 20–50 h. This linear trend appeared also after 35–50 h at 850°C. The activation energy was found to be 238.4 kJ/mole. At the lowest oxidation temperature (650°C), a disconnected oxide layer was observed. These variations in the response of Ti67 alloy to the different thermal oxidation conditions are worthy of consideration when modifying the surfaces for biomedical applications.
Collapse
Affiliation(s)
- Lamiaa Z. Mohamed
- Mining, Petroleum, and Metallurgical Engineering Department, Faculty of Engineering Cairo University Giza Egypt
| | | | - Shimaa El‐Hadad
- Department of Casting Technology Central Metallurgical Research and Development Institute (CMRDI) P.O. 87 Helwan Egypt
| |
Collapse
|
4
|
Gouvea EDS, Rossi MC, Escuder AV, Afonso CRM, Borrás VA. Relation between Mechanical Milling Parameters in Phase Transformation and Oxygen Content in Ti–Nb–Mo Powders for Posterior Sintering. Metals 2022; 12:1238. [DOI: 10.3390/met12081238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The influence of open vessels during milling for 12, 24, 40 and 60 h on microstructure homogeneity and oxygen content effect in the β Ti–Nb–Mo system microstructure were studied. The β phase increased with longer milling times and the strain hardening on particles was verified at 60 h when agglomeration was greater and was also noticed after 40 h in the continuous mode. Oxygen content dropped slightly until 40 h and increased after 60 h, a result linked with the observed hardening. For 40 h in the continuous mode, the oxygen content was noted near 12 h, 24 h and 40 h with high hardness values. For the sintered parts, the α phase and oxygen content significantly increased in all samples. Microhardness-sintered samples decreased compared to sample powders due to grain growth during the sintering. Bending strength was higher at 60 h with more oxygen and α phase content. After 40 h in the continuous mode, more suitable mechanical properties were reached because hardness and bending strength were closer to bone tissue, which was associated with strain hardening and a small crystallite size.
Collapse
|
5
|
Liu C, Lu W, Xia W, Du C, Rao Z, Best JP, Brinckmann S, Lu J, Gault B, Dehm G, Wu G, Li Z, Raabe D. Massive interstitial solid solution alloys achieve near-theoretical strength. Nat Commun 2022; 13:1102. [PMID: 35232964 DOI: 10.1038/s41467-022-28706-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 01/31/2022] [Indexed: 11/15/2022] Open
Abstract
Interstitials, e.g., C, N, and O, are attractive alloying elements as small atoms on interstitial sites create strong lattice distortions and hence substantially strengthen metals. However, brittle ceramics such as oxides and carbides usually form, instead of solid solutions, when the interstitial content exceeds a critical yet low value (e.g., 2 at.%). Here we introduce a class of massive interstitial solid solution (MISS) alloys by using a highly distorted substitutional host lattice, which enables solution of massive amounts of interstitials as an additional principal element class, without forming ceramic phases. For a TiNbZr-O-C-N MISS model system, the content of interstitial O reaches 12 at.%, with no oxides formed. The alloy reveals an ultrahigh compressive yield strength of 4.2 GPa, approaching the theoretical limit, and large deformability (65% strain) at ambient temperature, without localized shear deformation. The MISS concept thus offers a new avenue in the development of metallic materials with excellent mechanical properties. Interstitials can substantially strengthen metals. Here the authors show a massive interstitial solid solution (MISS) approach enabling a model multicomponent alloy to achieve near-theoretical strength together with large deformability.
Collapse
|
6
|
|
7
|
Tang L, Fan J, Kou H, Tang B, Li J. Effect of Oxygen Variation on High Cycle Fatigue Behavior of Ti-6Al-4V Titanium Alloy. Materials (Basel) 2020; 13:E3858. [PMID: 32882907 DOI: 10.3390/ma13173858] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/19/2020] [Accepted: 08/19/2020] [Indexed: 12/03/2022]
Abstract
The element oxygen is expected to be a low-cost, strengthening element of titanium alloys due to its strong solid solution strengthening effect. High cycle fatigue behaviors of Ti-6Al-4V alloys with different oxygen contents (0.17%, 0.20%, 0.23% wt.%) were investigated in this paper. The results illustrated that Ti-6Al-4V-0.20O alloy possesses the highest fatigue strength and the lowest fatigue crack propagation rate. The fatigue fracture morphology verified that the fatigue cracks propagated transgranularly in both Ti-6Al-4V-0.17O and Ti-6Al-4V-0.20O alloys, and the fatigue cracks tended to extend intergranularly in the Ti-6Al-4V-0.23O alloy. The maximum nano-hardness varied from the <0001> direction to the <1¯21¯0> and <011¯0> directions with the increasing oxygen content, which suggested that the dominant slip system varied from prismatic slip to pyramidal slip. The number of the <c→+a→> type dislocations increased with the oxygen content, which indicated that the number of the first-order pyramidal and the second-order pyramidal <c→+a→> slip systems increased. The oxygen can significantly change the fatigue fracture mechanism of Ti-6Al-4V alloy: From transgranular fracture to intergranular fracture. These results are expected to provide valuable reference for the optimization of the composition and mechanical properties of titanium alloys.
Collapse
|
8
|
Abstract
Binary Ti-Fe alloys with 5-25 mass% Fe were prepared, and subjected to reciprocating wear test. The aim of this study was to investigate the relationship between mechanical properties and the wear resistance of titanium and Ti-Fe alloys. The dimensions (length, width and depth) of wear marks on Ti-Fe alloys were less than those observed on pure Ti specimen. Wear resistance of Ti-Fe alloys was better than that of pure titanium. It was established that hardness was the main factor that influenced wear resistance of Ti-Fe alloys. Single β Ti-Fe alloys showed better wear resistance than α+β Ti-Fe alloys. Increase in concentration of Fe in the β phase of Ti-Fe alloys leads to improved wear resistance of the alloy. Ti-Fe alloys with 11-15 mass% Fe form ideal candidates for fabrication of dental titanium alloys with excellent wear resistance.
Collapse
Affiliation(s)
- Hirofumi Yamaguchi
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry.,Division of Dental Biomaterials, Tohoku University Graduate School of Dentistry
| | - Masatoshi Takahashi
- Division of Dental Biomaterials, Tohoku University Graduate School of Dentistry
| | - Keiichi Sasaki
- Division of Advanced Prosthetic Dentistry, Tohoku University Graduate School of Dentistry
| | - Yukyo Takada
- Division of Dental Biomaterials, Tohoku University Graduate School of Dentistry
| |
Collapse
|
9
|
Pellizzari M, Jam A, Tschon M, Fini M, Lora C, Benedetti M. A 3D-Printed Ultra-Low Young's Modulus β-Ti Alloy for Biomedical Applications. Materials (Basel) 2020; 13:E2792. [PMID: 32575750 DOI: 10.3390/ma13122792] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/14/2020] [Accepted: 06/17/2020] [Indexed: 02/07/2023]
Abstract
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.
Collapse
|
10
|
Todaro CJ, Easton MA, Qiu D, Zhang D, Bermingham MJ, Lui EW, Brandt M, StJohn DH, Qian M. Grain structure control during metal 3D printing by high-intensity ultrasound. Nat Commun 2020; 11:142. [PMID: 31919347 DOI: 10.1038/s41467-019-13874-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 12/04/2019] [Indexed: 11/08/2022] Open
Abstract
Additive manufacturing (AM) of metals, also known as metal 3D printing, typically leads to the formation of columnar grain structures along the build direction in most as-built metals and alloys. These long columnar grains can cause property anisotropy, which is usually detrimental to component qualification or targeted applications. Here, without changing alloy chemistry, we demonstrate an AM solidification-control solution to printing metallic alloys with an equiaxed grain structure and improved mechanical properties. Using the titanium alloy Ti-6Al-4V as a model alloy, we employ high-intensity ultrasound to achieve full transition from columnar grains to fine (~100 µm) equiaxed grains in AM Ti-6Al-4V samples by laser powder deposition. This results in a 12% improvement in both the yield stress and tensile strength compared with the conventional AM columnar Ti-6Al-4V. We further demonstrate the generality of our technique by achieving similar grain structure control results in the nickel-based superalloy Inconel 625, and expect that this method may be applicable to other metallic materials that exhibit columnar grain structures during AM.
Collapse
|
11
|
Acharya S, Bahl S, Dabas SS, Hassan S, Gopal V, Panicker AG, Manivasagam G, Suwas S, Chatterjee K. Role of aging induced α precipitation on the mechanical and tribocorrosive performance of a β Ti-Nb-Ta-O orthopedic alloy. Mater Sci Eng C Mater Biol Appl 2019; 103:109755. [PMID: 31349485 DOI: 10.1016/j.msec.2019.109755] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/30/2019] [Accepted: 05/14/2019] [Indexed: 11/21/2022]
Abstract
A low modulus β Ti-Nb-Ta-O alloy was subjected to heat treatment to investigate its phase stability upon aging. The resultant effect on the mechanical and functional properties was systematically evaluated. The aging of the β-only microstructure, obtained by solutionizing and quenching, resulted in the formation of ultrafine α-precipitates with increasing order of size as the aging temperature increased from 400 °C to 600 °C. The variation in the size of α-precipitates effected the mechanical properties at the three different aging temperature. The highest hardening observed at 400 °C was associated with macroscopic embrittlement, whereas age softening was observed in samples aged at 600 °C due to coarsening of precipitates and softening of the β-matrix. In contrast, aging at 500 °C resulted in about 32% increase in tensile strength from the β-solutionized condition. As the samples aged at 500 °C showed optimum combination of mechanical properties among the aged samples, these were further characterized for their electrochemical, tribological and biological responses. The fretting wear studies showed that the wear rate of the solution-treated samples increased after aging due to the higher corrosion rate leading to a higher rate of tribocorrosive dissolution and formation of a transfer layer harder than that of solution treated sample. The Ti-Nb-Ta-O alloy supported the attachment and proliferation of osteoblasts similar to that on commercially pure Ti. Taken together, this work provides new insights into the preparation of next-generation Ti alloys for biomedical applications with high strength and low modulus through microstructural control induced by heat treatment.
Collapse
|
12
|
Zhang C, Yang F, Guo Z, Wang H, Lu B. Oxygen scavenging, grain refinement and mechanical properties improvement in powder metallurgy titanium and titanium alloys with CaB6. POWDER TECHNOL 2018; 340:362-9. [DOI: 10.1016/j.powtec.2018.09.054] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
|
13
|
Cheng A, Goodwin WB, deGlee BM, Gittens RA, Vernon JP, Hyzy SL, Schwartz Z, Sandhage KH, Boyan BD. Surface modification of bulk titanium substrates for biomedical applications via low-temperature microwave hydrothermal oxidation. J Biomed Mater Res A 2017; 106:782-796. [PMID: 29067777 DOI: 10.1002/jbm.a.36280] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 09/24/2017] [Accepted: 10/19/2017] [Indexed: 01/30/2023]
Abstract
Micro-to-nanoscale surface topographies of orthopaedic and dental implants can affect fluid wetting and biological response. Nanoscale features can be superimposed on microscale roughness of titanium (Ti) surfaces at high temperatures, resulting in increased osteoblast differentiation. However, high temperatures can compromise mechanical properties of the bulk material. Here, we have developed a novel low-temperature microwave hydrothermal (MWHT) oxidation process for nanomodification of microrough (SLA) Ti surfaces. Nanoscale protuberances (20 -100 nm average diameter) were generated on SLA surfaces via MWHT treatment at 200°C in H2 O, or in aqueous solutions of H2 O2 or NH4 OH, for times ranging from 1 to 40 h. The size, shape, and crystalline content of the nanoprotuberances varied with the solution used and treatment time. The hydrophilicity of all MWHT-modified surfaces was dramatically enhanced. MG63 and normal human osteoblasts (NHOsts) were cultured on MWHT-treated SLA surfaces. While most responses to MWHT-modified surfaces were comparable to those seen on SLA controls, the MWHT-generated nanotopography reduced osteocalcin production by NHOst cells, suggesting that specific nanotopographic characteristics differentially mediate osteoblast phenotypic expression. MWHT processing provides a scalable, low-temperature route for tailoring nanoscale topographies on microroughened titanium implant surfaces with significantly enhanced wetting by water, without degrading the microscale surface structure of such implants. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 782-796, 2018.
Collapse
Affiliation(s)
- Alice Cheng
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA.,Department of Biomedical Engineering, Emory University, Atlanta, GA.,Department of Biomedical Engineering, Peking University, Beijing Shi, China
| | - W Brandon Goodwin
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA.,Department of Physics, Fisk University, Nashville, TN
| | - Ben M deGlee
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA
| | - Rolando A Gittens
- Biodiversity and Drug Discovery Center, Institute for Scientific Research and High Technology Services (INDICASAT), Clayton, Panama
| | | | - Sharon L Hyzy
- Department of Biomedical Engineering, Virginia Commonwealth University, VS
| | - Zvi Schwartz
- Department of Biomedical Engineering, Virginia Commonwealth University, VS.,Department of Periodontics, University of Texas Health Science Center at San Antonio, TX
| | - Kenneth H Sandhage
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA.,School of Materials Engineering, Purdue University, W. Lafayette, IN
| | - Barbara D Boyan
- Department of Biomedical Engineering, Georgia Institute of Technology, Atlanta, GA.,Department of Biomedical Engineering, Virginia Commonwealth University, VS
| |
Collapse
|
14
|
Baillieux J, Poquillon D, Malard B. Relationship between the volume of the unit cell of hexagonal-close-packed Ti, hardness and oxygen content after α-case formation in Ti–6Al–2Sn–4Zr–2Mo–0.1Si alloy. J Appl Crystallogr 2016. [DOI: 10.1107/s1600576715022906] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
In this study, the influence of oxygen diffusion on the physical properties of Ti–6Al–2Sn–4Zr–2Mo–0.1Si was examined. Measurements were carried out directly on sample cross sections which were preoxidized at high temperature. The lattice parameter evolution was measured using synchrotron X-ray diffraction and was coupled with microhardness and electron probe microanalyzer results with the aim of highlighting their relationships. The results show that the hardness and oxygen gradients along the oxygen diffusion zone in the alloy are similar to the evolution of the α-phase unit-cell volume quantified by X-ray diffraction. Linear relationships were found between these three parameters.
Collapse
|
15
|
Hazell PJ, Appleby-Thomas GJ, Wielewski E, Escobedo JP. The shock and spall response of three industrially important hexagonal close-packed metals: magnesium, titanium and zirconium. Philos Trans A Math Phys Eng Sci 2014; 372:20130204. [PMID: 25071240 DOI: 10.1098/rsta.2013.0204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Magnesium, titanium and zirconium and their alloys are extensively used in industrial and military applications where they would be subjected to extreme environments of high stress and strain-rate loading. Their hexagonal close-packed (HCP) crystal lattice structures present interesting challenges for optimizing their mechanical response under such loading conditions. In this paper, we review how these materials respond to shock loading via plate-impact experiments. We also discuss the relationship between a heterogeneous and anisotropic microstructure, typical of HCP materials, and the directional dependency of the elastic limit and, in some cases, the strength prior to failure.
Collapse
Affiliation(s)
- P J Hazell
- School of Engineering and Information Technology, UNSW Canberra at the Australian Defence Force Academy, UNSW Australia, Northcott Drive, Canberra, ACT 2600, Australia
| | - G J Appleby-Thomas
- Centre for Defence Engineering, Cranfield University, Defence Academy of the United Kingdom, Shrivenham, Swindon SN6 8LA, UK
| | - E Wielewski
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - J P Escobedo
- School of Engineering and Information Technology, UNSW Canberra at the Australian Defence Force Academy, UNSW Australia, Northcott Drive, Canberra, ACT 2600, Australia
| |
Collapse
|
16
|
Wang R, Welsch G. Evaluation of an experimental Ti-Co alloy for dental restorations. J Biomed Mater Res B Appl Biomater 2013; 101:1419-27. [PMID: 23744579 DOI: 10.1002/jbm.b.32961] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 03/15/2013] [Accepted: 03/27/2013] [Indexed: 11/08/2022]
Abstract
Precision and surface quality of pure titanium (Ti) castings for dental and biomedical uses are limited because of the high melting temperature and the violent reactivity of Ti with mold materials during casting procedures. This feasibility study evaluates an experimental low-melting Ti-Co alloy in term of its microstructure and physical and mechanical properties. Tensile samples of Ti-12 wt % Co alloy were cast under a protective argon atmosphere. The melting range of the cast samplers was determined. Cast samples were annealed at 1010°C for various time intervals in order to homogenize microstructures. Microstructures were examined by optical and scanning electron microscopy. Tensile strength and microhardness tests were performed and correlated with microstructures resulting from annealing processes. Ti2Co intermetallic compound coexisted with Ti-Co solid solution in all samples. The melting range of the alloy was 1062-1088°C, which is 568°C lower than that of Ti. The thickness of the surface oxide scale on cast samples was dramatically reduced to 1-3 μm because of the low-melting nature of the alloy. Solution treatment at 1010°C for 100 h yields the highest tensile strength. Ultimate tensile strength is measured from 852 to 1240 MPa which is stronger than currently used dental alloys. Microhardness values were ranged from 341 to 488 KHN and elongation was from 1.2 to 1.8%. Both microhardness and percentage elongation are similar to those of dental Co-Cr alloys. One hundred hours of annealing dissolved dendritic boundaries and transformed the alloy to a more microductitle matrix, however, the intermetallic compound of Ti2Co remained.
Collapse
Affiliation(s)
- Russell Wang
- Department of Comprehensive Care, Case Western Reserve University, School of Dental Medicine, Cleveland, Ohio
| | | |
Collapse
|
17
|
Affiliation(s)
- Yasuko TAKAYAMA
- Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine
| | - Rie NOMOTO
- Department of Dental Engineering, Tsurumi University School of Dental Medicine
| | | | - Chikahiro OHKUBO
- Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine
| |
Collapse
|
18
|
Abstract
AbstractExcimer laser processing results in very rapid solidification of metal surfaces. In addition to mixing or segregation processes, rapid heat treatment can result in phase transformations which yield beneficial surface properties. We have investigated the effect of pulsed excimer laser radiation on the microstructure and surface hardness of Ti-6A1-4V. This material undergoes a well defined martensite transformation during rapid quenching from temperatures in the β phase field. The depth of the transformed layer is thus a marker for the temperature profile during processing. We find that the depth of the transformed layer agrees well with a simple 1-D calculation of heat flow following the laser pulse. As measured by the nanoindenter, we find that the surface martensite is softer than the mechanically polished alloy. Multiple pulse processing at high fluences results in an increase in surface hardness, but at a depth much less than that of the martensite, suggesting an independent mechanism.
Collapse
|
19
|
Abstract
We developed a new titanium alloy with high strength, low elastic modulus, high elasticity and
plasticity after cold working. Thermo mechanical processing, ageing, recrystallization after cold working was
conducted to change the mechanical properties. The release of the elastic deformation energy after cold
working is help to get the low modulus, however, the precipitation of α phase hamper the formation and
propagation of the fatigue crack. Recrystallization after cold working could refine the grain size from 100μm to
1~5μm. Cold working after recrystallization absolutely restricts the propagation of the fatigue crack. As a
result, the fatigue strength was increased, and the same time, it keeps the low elastic modulus.
Collapse
|
20
|
Abstract
STATEMENT OF PROBLEM Titanium and its alloys are more commonly used in prosthodontics and welding has become the most common modality for their joining. Studies on the welding of titanium and its alloys have not quantified this value, though its importance has been suggested. PURPOSE This study compared the strength and properties of the joint achieved at various butt joint gaps by the arc-welding of cast Ti-6Al-4V alloy tensile bars in an argon atmosphere. MATERIAL AND METHODS Forty of 50 specimens were sectioned and welded at four gaps. All specimens underwent tensile testing to determine ultimate tensile strength and percentage elongation, then oxygen analysis and scanning electron microscopy. RESULTS As no more than 3 samples in any group of 10 actually fractured in the weld itself, a secondary analysis that involved fracture location was initiated. There were no differences in ultimate tensile strength or percentage elongation between specimens with weld gaps of 0.25, 0.50, 0.75, and 1.00 mm and the as-cast specimens. There were no differences in ultimate tensile strength between specimens fracturing in the weld and those fracturing in the gauge in welded specimens; however, as-cast specimens demonstrated a higher ultimate tensile strength than welded specimens that fractured in the weld. Specimens that fractured in the weld site demonstrated less ductility than those that fractured in the gauge in both welded and as-cast specimens, as confirmed by scanning electron microscopy examination. The weld wire showed an oxygen scavenging effect from the as-cast parent alloy. CONCLUSIONS The effects of the joint gap were not significant, whereas the characteristics of the joint itself were, which displayed slightly lower strength and significantly lower ductility (and thus decreased toughness). The arc-welding of cast titanium alloy in argon atmosphere appears to be a reliable and efficient prosthodontic laboratory modality producing predictable results, although titanium casting and joining procedures must be closely controlled to minimize heat effects and oxygen contamination.
Collapse
Affiliation(s)
- J C Taylor
- Division of Prosthodontics, Faculty of Dentistry, Dalhousie University, Halifax, Canada
| | | | | | | |
Collapse
|
21
|
Abstract
STATEMENT OF PROBLEM Concerns of laser welding for titanium dental prostheses are the limited depth of laser beam penetration and extensive surface damage. PURPOSE This study used numerical heat transfer simulation to explain this behavior and offers an alternate multiple-pulsed method. MATERIAL AND METHODS A one-dimensional finite difference analysis was used to simulate heat transfer in pure titanium and gold during laser welding with a custom-constructed software program. RESULTS The thermal gradient profiles revealed the problem to be inherent in titanium's low thermal conductivity; gold did not have this problem. Time-elapsed multiple pulses on titanium relieved this problem by giving the energy time to diffuse into the depth of the material. CONCLUSIONS With single-pulse laser irradiation on titanium, an increase in power could not greatly increase melting depth. The excess energy only vaporized the material surface.
Collapse
Affiliation(s)
- R R Wang
- Department of Restorative Dentistry, Case Western Reserve University, School of Dentistry, Cleveland, Ohio, USA
| | | |
Collapse
|
22
|
Abstract
STATEMENT OF PROBLEM Titanium-ceramic bonding is an unsolved problem for the current use of titanium-ceramic restorations. PURPOSE The purpose of the study was to characterize oxide formation on titanium surfaces at porcelain sintering temperatures and to determine the effect of chromium coating methods on titanium oxide formation. MATERIAL AND METHODS Sputter coating and electroplating methods of chromium application were compared and combined. RESULTS Porous, weak titanium oxide formation on uncoated samples was demonstrated at porcelain sintering temperatures. Groups with chromium coating as an oxygen diffusion barrier exhibited lower oxidation rates, except samples coated by sputtering alone. Temperature effect was found to have the greatest significance on titanium oxidation rate. The overall lowest oxidation rate was located in the group that had chromium coating by the combined coating method and was oxidized at 750 degrees C. CONCLUSION The electroplating method requires further investigation and development so that a uniform chromium layer can be deposited on titanium.
Collapse
Affiliation(s)
- R R Wang
- Department of Restorative Dentistry, School of Dentistry, Case Western Reserve University, Cleveland, Ohio, USA
| | | |
Collapse
|
23
|
Abstract
Titanium has a number of desirable properties for dental applications that include low density, excellent biocompatibility, and corrosion resistance. However, joining titanium is one of the practical problems with the use of titanium prostheses. Dissolved oxygen and hydrogen may cause severe embrittlement in titanium materials. Therefore the conventional dental soldering methods that use oxygen flame or air torch are not indicated for joining titanium materials. This study compared laser, tungsten inert gas, and infrared radiation heating methods for joining both pure titanium and Ti-6Al-4V alloy. Original rods that were not subjected to joining procedures were used as a control method. Mechanical tests and microstructure analysis were used to evaluate joined samples. Mechanical tests included Vickers microhardness and uniaxial tensile testing of the strength of the joints and percentage elongation. Two-way analysis of variance and Duncan's multiple range test were used to compare mean values of tensile strength and elongation for significant differences (p < or = 0.05). Tensile rupture occurred in the joint region of all specimens by cohesive failure. Ti-6Al-4V samples exhibited significantly greater tensile strength than pure titanium samples. Samples prepared by the three joining methods had markedly lower tensile elongation than the control titanium and Ti-6Al-4V rods. The changes in microstructure and microhardness were studied in the heat-affected and unaffected zones. Microhardness values increased in the heat-affected zone for all the specimens tested.
Collapse
Affiliation(s)
- R R Wang
- Department of Restorative Dentistry, Case Western Reserve University, School of Dentistry, Cleveland, OH 44106-4905, USA
| | | |
Collapse
|
24
|
|
25
|
|
26
|
Liu Z, Welsch G. Literature Survey on Diffusivities of Oxygen, Aluminum, and Vanadium in Alpha Titanium, Beta Titanium, and in Rutile. ACTA ACUST UNITED AC 1988. [DOI: 10.1007/bf02628396] [Citation(s) in RCA: 105] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|