Effect of Small Iron, Chromium and Boron Additions as Alloying Elements on Microstructure and Mechanical Properties of Ni3Al

2007 ◽  
Vol 23 ◽  
pp. 123-126
Author(s):  
Radu L. Orban ◽  
Mariana Lucaci

This paper investigates the effect of Fe, Cr and B additions, in small proportions, as alloying elements in Ni3Al with the purpose to reduce its intrinsic fragility and extrinsic embrittlement and to enhance, in the same time, its mechanical properties. It represents a development of some previous research works of the authors, proving that Ni3Al-Fe-Cr-B alloys obtained by reactive synthesis (SHS) starting from Mechanically Alloyed powder mixtures have superior both room temperature tensile strength and ductility, and compression ones at temperatures up to 800 °C, than pure Ni3Al. These create premises for their using as superalloys substitutes.

2011 ◽  
Vol 686 ◽  
pp. 96-100
Author(s):  
Shu Bo Li ◽  
Han Li ◽  
Jian Hui Li ◽  
Wen Bo Du ◽  
Zhao Hui Wang

The microstructures and mechanical properties of the Mg-Zn-Er alloys have been investigated. The results show that the alloying elements (Zn/Er) with different ratio have a great effect on the microstructure and mechanical properties of the magnesium alloys, especially for the phase constitutes. Furthermore, the more attractive result is that the quasicrystalline phase, as the main secondary phase, precipitates during solidification in the alloy with addition of Zn/Er ration of 6. The cast Mg-5Zn-0.83Er alloy exhibits the ultimate tensile strength and yield tensile strength are 190MPa and 80MPa at room temperature, respectively, with an elongation of 15%.


2009 ◽  
Vol 23 (06n07) ◽  
pp. 783-789 ◽  
Author(s):  
C. J. BETTLES ◽  
T. PUEHRINGER ◽  
A. J. MORTON ◽  
D. TOMUS ◽  
M. A. GIBSON

Alloys in the dilute Ti - Al - Mn system, which are considered to be near-α alloys, possess an attractive combination of strength and ductility, with the room temperature properties being intermediate between CP Ti and Ti -6 Al -4 V . Low levels of Fe are often tolerated in such alloys, but rarely introduced as deliberate alloying additions (with the exception of CP Ti grades), and from a processing perspective, it may indeed be desirable to have higher tolerances for Fe as it is often a common contaminant which must be controlled. In this presentation, the effect of 0.3 wt .% Fe on the microstructure and behavior of a Ti -0.75 wt .% Al -0.75 wt .% Mn is reported. It was found that annealing in the (α+β) phase field can lead to an increase in the ductility of the alloy without having a detrimental effect on the tensile strength.


2005 ◽  
Vol 297-300 ◽  
pp. 250-256
Author(s):  
Il Ho Kim ◽  
Yong Hwan Kim ◽  
C.S. Kim

The effects of adding Al, Y2O3 and the use of H2O as a PCA (process control agent), on the mechanical properties of mechanically alloyed Ni20Cr20Fe5Nb alloy were studied. The addition of Y2O3 and Al caused an increase in the tensile strength at room temperature, 400°C and 600°C. However, it was confirmed that the increase of tensile strength at room temperature and 400°C was predominantly caused by addition of Y2O3, while that at 600°C was mainly due to addition of Al. These results can be attributed to the dispersion strengthening of Y2O3, preventing the formation of Cr2O3 and the change of fracture mode at 600°C by the addition of Al. Therefore, the Ni20Cr20Fe5Nb2Al alloy using H2O as a PCA showed superior tensile strength at room temperature, 400°C and 600°C. The increase in the tensile strength at room temperature and 400°C can be attributed to the strengthening of the solid solution induced by the increase in the amount of Nb solid solution, resulting from the prevention of NbC formation, while the increase in the tensile strength at 600°C can be attributed to the strengthening of the grain boundary afforded by the presence of Al1.54Cr0.46O3 formed by the addition of Al. After aging treatment for 10 hours at 600°C, g²(Ni3Nb) precipitates were formed in the Ni20Cr20Fe5Nb2Al alloy in which H2O used as the PCA, and the formation of these precipitates caused an increase in hardness.


2011 ◽  
Vol 311-313 ◽  
pp. 43-47
Author(s):  
Yuong Chen ◽  
Chang Jiang Zhang ◽  
Rahoma Hasan K.S ◽  
Fan Tao Kong ◽  
Shu Long Xiao ◽  
...  

Ti-6Al-2.5Sn-4Zr-0.7Mo-0.3Si-0.3Y alloy matrix composite reinforced with 7%vol TiB whiskers was fabricated by Induction Skull Melting (ISM) technique and one-direction forged technology utilizing the reaction between titanium and TiB2. The microstructure, room temperature and high temperature mechanical properties have been presented and discussed. Microstructural analysis of the composites revealed that the microstructure was significantly refined and TiB whiskers were made to align the longitudinal direction after forging. It shows that the tensile strength and ductility of the composites has a significant improvement, especially at room temperature.


2005 ◽  
Vol 488-489 ◽  
pp. 177-180
Author(s):  
T. Liu ◽  
Yan Dong Wang ◽  
Shi Ding Wu ◽  
Shou Xin Li ◽  
Ru Lin Peng ◽  
...  

The room temperature tensile strength and ductility of Mg-3.3%Li alloy were improved simultaneously by two kinds of different equal channel angular pressing (ECAP) treatments. Microstructural analyses showed that grain refinement and texture modification are the principal reasons for the improvement of mechanical properties.


2020 ◽  
Vol 58 (7) ◽  
pp. 459-465
Author(s):  
Jong-hun Kim ◽  
Jae-Kwon Kim ◽  
Seong-Woong Kim ◽  
Yong-Ho Park ◽  
Seung Eon Kim

The microstructure and mechanical properties of a newly developed, β-phase containing TiAl alloy have been studied through hot working and post heat treatment to enhance room temperature ductility and strength. The controlled microstructures hadthree types of structure, fully lamellar, nearly lamellar and duplex, and were produced by cyclic heat-treatment in a single α region and (α+γ) region after a hot-forging process in high temperature (α+β) region. As a result of the room temperature tensile test, the fully lamellar structure exhibited a tensile strength of 622 MPa and ductility of 0.62%. The duplex structure had a tensile strength of 787 MPa and ductility of 1.22%, while the nearly lamellar structure showed a tensile strength of 880 MPa and ductility of 1.76%. In the room temperature tensile test, the nearly lamellar structure exhibited excellent tensile strength and ductility. The strength and ductility were increased by decreasing grain size and β / B2 phase fraction. The newly developed TiAl alloy showed higher tensile values compared with the previous TiAl alloys. The relationship between microstructure and room temperature tensile properties of the newly developed β-phase containing TiAl alloy was examined, and the best approach for hot working and post heat-treatment to obtain the most balanced mechanical properties was proposed.


Materials ◽  
2021 ◽  
Vol 14 (24) ◽  
pp. 7557
Author(s):  
Yuan Miao ◽  
Chao Wang ◽  
Minghui Wang ◽  
Hai Deng ◽  
Pinkui Ma ◽  
...  

Calcium (Ca), with abundant and cheap reserves, is a potential element to facilitate the further application of Mg-Al-Sn based alloys. Here, effects of Ca content on the microstructure and tensile properties of Mg-2.0Al-0.8Sn (wt.%) alloys were systematically studied. The experimental results illustrated that the strength, ductility and isotropy of the alloys improved simultaneously with the increase of Ca content. The better ductility and isotropy could be contributed to the weakened texture via particle stimulation nucleation mechanism. The higher strength benefited from the combination of finer grains, more precipitates and residual dislocation density. Eventually, the Mg-2.0Al-0.8Sn-0.5Ca (wt.%) alloy showed the best room-temperature balance of strength and ductility with a yield strength of ∼226.0 MPa, an ultimate tensile strength of ∼282.4 MPa and a fracture elongation of ∼20.2%, which has huge potential as an applicable low-cost high-performance magnesium alloy.


Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 31
Author(s):  
Hongxin Liao ◽  
Taekyung Lee ◽  
Jiangfeng Song ◽  
Jonghyun Kim ◽  
Fusheng Pan

The microstructures and mechanical properties of the Mg88.5Zn5Y6.5-XREX (RE = Yb and Ce, X = 0, 1.5, 3.0, and 4.5) (wt.%) alloys were investigated in the present study. Mg88.5Zn5Y6.5 is composed of three phases, namely, α-Mg, long-period stacking ordered (LPSO) phases, and intermetallic compounds. The content of the LPSO phases decreased with the addition of Ce and Yb, and no LPSO phases were detected in Mg88.5Zn5Y2.0Yb4.5. The alloys containing the LPSO phases possessed a stratified microstructure and exhibited excellent mechanical properties. Mg88.5Zn5Y5.0Ce1.5 exhibited the highest creep resistance and mechanical strength at both room temperature and 200 °C, owing to its suitable microstructure and high thermal stability. The yield strength of Mg88.5Zn5Y5.0Ce1.5 at room temperature was 358 MPa. The ultimate tensile strength of Mg88.5Zn5Y5.0Ce1.5 at room temperature and 200 °C was 453 MPa and 360 MPa, respectively.


2012 ◽  
Vol 194 ◽  
pp. 187-193 ◽  
Author(s):  
J.M. Loureiro ◽  
Benilde F.O. Costa ◽  
Gerard Le Caër ◽  
Bernard Malaman

Ternary alloys, (Fe50−x/2Co50−x/2)Snx(x ≤ 33 at.%), are prepared by mechanical alloying from powder mixtures of the three elements. As-milled alloys are studied by X-ray diffraction and 57Fe and 119Sn Mössbauer spectroscopy. The solubility of Sn in near-equiatomic bcc FeCo is increased from ~0.5 at. % at equilibrium to ~20 at.% in the used milling conditions. The average 119Sn hyperfine magnetic field at room temperature is larger, for any x, than the corresponding fields in mechanically alloyed Fe-Sn solid solutions.


2006 ◽  
Vol 114 ◽  
pp. 91-96 ◽  
Author(s):  
Maxim Yu. Murashkin ◽  
M.V. Markushev ◽  
Julia Ivanisenko ◽  
Ruslan Valiev

The effects of equal channel angular pressing (ECAP), further heat treatment and rolling on the structure and room temperature mechanical properties of the commercial aluminum alloys 6061 (Al-0.9Mg-0.7Si) and 1560 (Al-6.5Mg-0.6Mn) were investigated. It has been shown that the strength of the alloys after ECAP is higher than that achieved after conventional processing. Prior ECAP solution treatment and post-ECAP ageing can additionally increase the strength of the 6061 alloy. Under optimal ageing conditions a yield strength (YS) of 434 MPa and am ultimate tensile strength (UTS) of 470 MPa were obtained for the alloy. Additional cold rolling leads to a YS and UTS of 475 and 500 MPa with 8% elongation. It was found that the post-ECAP isothermal rolling of the 1560 alloy resulted in the formation of a nano-fibred structure and a tensile strength (YS = 540 MPa and UTS = 635 MPa) that has never previously been observed in commercial non-heat treatable alloys.


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