Microstructure, Mechanical Properties, Creep and Corrosion Resistance of Mg-Gd-Y-Zr(-Ca) Alloys

The microstructure, mechanical properties, creep and corrosion resistance of Mg-Gd-Y-Zr(-Ca) alloys were studied. Small additions of 0.4-0.6 wt% Ca to Mg-(9-10)Gd-3Y-0.4Zr(wt.%) alloys led to a slight improvement in creep resistance and a remarkable increase in corrosion resistance, but an obvious decrease in elongation to fracture. UTS and TYS of the Mg-Gd-Y-Zr(-Ca) alloys are obviously higher than those of WE54, especially in the temperature range from room temperature to 200 oC. TEM images and corresponding energy dispersive x-ray spectra showed that the Ca element primarily segregated to the grain boundaries and existed in the cuboid-shaped particles with a trace concentration, and the small addition of Ca had no obvious effect on the orientation, morphology, and distribution of β′ phase, which is responsible for the peak hardness in Mg-Gd-Y-Zr alloys.

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Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

MRS Proceedings ◽

10.1557/proc-133-415 ◽

1988 ◽

Vol 133 ◽

Cited By ~ 3

Author(s):

K. S. Kumar ◽

S. K. Mannan

Keyword(s):

High Temperature ◽

Mechanical Alloying ◽

Mechanical Milling ◽

Room Temperature ◽

Crystalline Compound ◽

X Ray Diffraction ◽

X Ray ◽

Β Phase ◽

Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

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Assessment of Mechanical, Chemical, and Biological Properties of Ti-Nb-Zr Alloy for Medical Applications

Materials ◽

10.3390/ma14010126 ◽

2020 ◽

Vol 14 (1) ◽

pp. 126

Author(s):

Viktoria Hoppe ◽

Patrycja Szymczyk-Ziółkowska ◽

Małgorzata Rusińska ◽

Bogdan Dybała ◽

Dominik Poradowski ◽

...

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Base Material ◽

Biological Properties ◽

Β Phase ◽

Alloy Base ◽

Static Tensile ◽

Examination Methods ◽

13Zr Alloy ◽

Dental Applications

The purpose of this work is to obtain comprehensive reference data of the Ti-13Nb-13Zr alloy base material: its microstructure, mechanical, and physicochemical properties. In order to obtain extensive information on the tested materials, a number of examination methods were used, including SEM, XRD, and XPS to determine the phases occurring in the material, while mechanical properties were verified with static tensile, compression, and bending tests. Moreover, the alloy’s corrosion resistance in Ringer’s solution and the cytotoxicity were investigated using the MTT test. Studies have shown that this alloy has the structure α’, α, and β phases, indicating that parts of the β phase transformed to α’, which was confirmed by mechanical properties and the shape of fractures. Due to the good mechanical properties (E = 84.1 GPa), high corrosion resistance, as well as the lack of cytotoxicity on MC3T3 and NHDF cells, this alloy meets the requirements for medical implant materials. Ti-13Nb-13Zr alloy can be successfully used in implants, including bone tissue engineering products and dental applications.

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Physical and Mechanical Properties of Cement Paste Were Used Partially with Fly Ash and Kaolin Waste

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.866.199 ◽

2017 ◽

Vol 866 ◽

pp. 199-203

Author(s):

Chidchanok Chainej ◽

Suparut Narksitipan ◽

Nittaya Jaitanong

Keyword(s):

Mechanical Properties ◽

Fly Ash ◽

Room Temperature ◽

Physical And Mechanical Properties ◽

Partial Replacement ◽

X Ray Diffraction ◽

X Ray ◽

Lime Water ◽

Diffraction Patterns ◽

Iron Mold

The aims of this research were study the microstructures and mechanical properties for partial replacement of cement with Fly ash (FA) and kaolin waste (KW). Ordinary Portland cement were partially replaced with FA and KW in the range of 25-35% and 10-25% by weight of cement powder. The kaolin waste was ground for 180 minutes before using. The specimen was packing into an iron mold which sample size of 5×5×5 cm3. Then, the specimens were kept at room temperature for 24 hours and were moist cured in the incubation lime water bath at age of 3 days. After that the specimens were dry cured with plastic wrap at age of 3, 7, 14 and 28 days. After that the compounds were examined by x-ray diffraction patterns (XRD) and the microstructures were examined by scanning electron microscopy (SEM). The compressive strength was then investigated.

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X-Ray Investigations of the Low-Temperature Phases of the Organic Metals α- and β-(BEDT-TTF)2I3

Zeitschrift für Naturforschung A ◽

10.1515/zna-1986-1110 ◽

1986 ◽

Vol 41 (11) ◽

pp. 1319-1324 ◽

Cited By ~ 10

Author(s):

H. Endres ◽

H. J. Keller ◽

R. Swietlik ◽

D. Schweitzer ◽

K. Angermund ◽

...

Keyword(s):

Thermal Analysis ◽

Differential Thermal Analysis ◽

Room Temperature ◽

Unit Cell Volume ◽

Unit Cell ◽

Slight Variation ◽

X Ray ◽

Organic Metals ◽

Β Phase ◽

Α Phase

The structure of single crystals of the organic metals α- and β-(BEDT-TTF)2I3* was determined at 100 K, well below the phase transitions indicated by resistivity and thermopower measurements as well as by differential thermal analysis. In the α-phase no unusual change of the room temperature unit cell but a slight variation in the triiodide network and especially a more pronounced dimerization in one of the two donor stacks have been found. The β-phase develops a superstructure with a unit cell volume three times as large as that at room temperature and with pronounced distortions of the I3--ions.

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Microstructural and Mechanical Characterization of Al-0.80Mg-0.85Si-0.3Zr Alloy

Archives of Foundry Engineering ◽

10.1515/afe-2017-0133 ◽

2017 ◽

Vol 17 (4) ◽

pp. 73-78 ◽

Cited By ~ 1

Author(s):

F. Kahrıman ◽

M. Zeren

Keyword(s):

Mechanical Properties ◽

Automotive Industry ◽

Room Temperature ◽

Tensile Tests ◽

Direct Chill ◽

Peak Hardness ◽

Casting Method ◽

Industry Standard ◽

Three Stages

Abstract In this study, Al-0.80Mg-0.85Si alloy was modified with the addition of 0.3 wt.-% zirconium and the variation of microstructural features and mechanical properties were investigated. In order to produce the billets, vertical direct chill casting method was used and billets were homogenized at 580 °C for 6 h. Homogenized billets were subjected to aging practice following three stages: (i) solution annealing at 550 °C for 3 h, (ii) quenching in water, (iii) aging at 180 °C between 0 and 20 h. The hardness measurements were performed for the alloys following the aging process. It was observed that peak hardness value of Al-0.80Mg-0.85Si alloy increased with the addition of zirconium. This finding was very useful to obtain aging parameters for the extruded hollow profiles which are commonly used in automotive industry. Standard tensile tests were applied to aged profiles at room temperature and the results showed that modified alloy had higher mechanical properties compared to the non-modified alloy.

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Effect of Hot Forging and Different Cooling Rates on the Microstructure, Mechanical Properties of Carbon Steel Containing 0.8 and 1.2Al

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.622-623.174 ◽

2014 ◽

Vol 622-623 ◽

pp. 174-178

Author(s):

Ahmed Ismail Zaky Farahat ◽

Mohamed Kamal Elfawkhry

Keyword(s):

Mechanical Properties ◽

Carbon Steel ◽

Mechanical Testing ◽

Room Temperature ◽

Induction Furnace ◽

Hot Forging ◽

X Ray Diffraction ◽

Cooling Rates ◽

X Ray ◽

Sem Microstructure

Two alloys of steel containing nominally 0.45C-1.0Si-2.0Mn-0.8Al and 1.2Al were cast in open air induction furnace. Dilatation testing was carried out to recognize the effect on Aluminum on the different critically transformation temperatures. The alloys were hot forged at 1200°C and then subjected to different cooling rates. Mechanical testing was carried out at room temperature. Optical and SEM microstructure were observed. X-ray diffraction was conducted to observe the microstructure constituents.

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Effect of Nitrogen Addition on Mechanical Property of Ti-Cr-Sn Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.654-656.2126 ◽

2010 ◽

Vol 654-656 ◽

pp. 2126-2129 ◽

Cited By ~ 4

Author(s):

Yuichi Nakahira ◽

Tomonari Inamura ◽

Hiroyasu Kanetaka ◽

Shuichi Miyazaki ◽

Hideki Hosoda

Keyword(s):

Mechanical Properties ◽

Room Temperature ◽

Tensile Tests ◽

Nitrogen Addition ◽

N Addition ◽

X Ray Diffraction ◽

Solution Hardening ◽

X Ray ◽

Bcc Phase ◽

Cold Workability

Effect of nitrogen (N) addition on mechanical properties of Ti-Cr-Sn alloy was investigated in this study. Ti-7mol%Cr-3mol%Sn was selected and less than 0.5wt% of N were systematically added. The alloys were characterized by optical microscopy, X-ray diffraction analysis and tensile tests at room temperature. The apparent phase was β (bcc) phase, whereas the presence of precipitates was confirmed in 0.5wt%N-added alloy only which did not exhibit sufficient cold workability. The grain size was not largely affected by N addition being less than 0.5wt%. Tensile tests revealed that less than 0.5wt%N addition improves the strength which is due to the solution hardening by interstitial N atoms.

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Effects of Cooling Rate and Sn Addition on the Microstructure of Ti-Nb-Sn Alloys

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.172-174.190 ◽

2011 ◽

Vol 172-174 ◽

pp. 190-195 ◽

Cited By ~ 8

Author(s):

Giorgia T. Aleixo ◽

Eder S.N. Lopes ◽

Rodrigo Contieri ◽

Alessandra Cremasco ◽

Conrado Ramos Moreira Afonso ◽

...

Keyword(s):

Mechanical Properties ◽

Cooling Rate ◽

Melting Furnace ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Β Phase ◽

Arc Melting ◽

Ti Alloys ◽

Ω Phase

Ti-based alloys present unique properties and hence, are employed in several industrial segments. Among Ti alloys, β type alloys form one of the most versatile classes of materials in relation to processing, microstructure and mechanical properties. It is well known that heat treatment of Ti alloys plays an important role in determining their microstructure and mechanical behavior. The aim of this work is to analyze microstructure and phases formed during cooling of β Ti-Nb-Sn alloy through different cooling rates. Initially, samples of Ti-Nb-Sn system were prepared through arc melting furnace. After, they were subjected to continuous cooling experiments to evaluate conditions for obtaining metastable phases. Microstructure analysis, differential scanning calorimetry and X-ray diffraction were performed in order to evaluate phase transformations. Depending on the cooling rate and composition, α” martensite, ω phase and β phase were obtained. Elastic modulus has been found to decrease as the amount of Sn was increased.

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Influences of Solution Temperatures on Microstructure and Mechanical Properties of near α Titanium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1035.89 ◽

2021 ◽

Vol 1035 ◽

pp. 89-95

Author(s):

Chao Tan ◽

Zi Yong Chen ◽

Zhi Lei Xiang ◽

Xiao Zhao Ma ◽

Zi An Yang

Keyword(s):

Mechanical Properties ◽

Titanium Alloy ◽

High Temperature ◽

Room Temperature ◽

Solution Temperature ◽

Vacuum Induction Melting ◽

Induction Melting ◽

Β Phase ◽

Α Phase ◽

New Type

A new type of Ti-Al-Sn-Zr-Mo-Si series high temperature titanium alloy was prepared by a water-cooled copper crucible vacuum induction melting method, and its phase transition point was determined by differential thermal analysis to be Tβ = 1017 °C. The influences of solution temperature on the microstructures and mechanical properties of the as-forged high temperature titanium alloy were studied. XRD results illustrated that the phase composition of the alloy after different heat treatments was mainly α phase and β phase. The microstructures showed that with the increase of the solution temperature, the content of the primary α phase gradually reduced, the β transformation structure increased by degrees, then, the number and size of secondary α phase increased obviously. The tensile results at room temperature (RT) illustrated that as the solution temperature increased, the strength of the alloy gradually increased, and the plasticity decreased slightly. The results of tensile test at 650 °C illustrated that the strength of the alloy enhanced with the increase of solution temperature, the plasticity decreased first and then increased, when the solution temperature increased to 1000 °C, the alloy had the best comprehensive mechanical properties, the tensile strength reached 714.01 MPa and the elongation was 8.48 %. Based on the room temperature and high temperature properties of the alloy, the best heat treatment process is finally determined as: 1000 °C/1 h/AC+650 °C/6 h/AC.

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