scholarly journals The The effect of iron on precipitation hardening in the Cu-Ni-Mn alloys

2021 ◽  
Vol 22 (3) ◽  
pp. 487-493
Author(s):  
O.V. Sukhova
Keyword(s):  
Precipitation Hardening ◽  
Annealing Temperature ◽  
Volume Fraction ◽  
Iron Oxidation ◽  
Quantitative Metallography ◽  
Structure And Properties ◽  
X Ray ◽  
Temperature Ranges ◽  
Fe Alloys ◽  
Scanning Electron

The peculiarities in the structure and properties formation of precipitation-hardened Сu–Ni–Mn–Fe alloys within the concentration range of Ni (19.3–21.0 %), Mn (19.5–20.5 %), Fe (0.6–2.7 %), Cu – balance (in wt. %) were investigated in this work. The methods of quantitative metallography, X-ray analysis, scanning electron microscopy, energy-dispersive spectroscopy and differential thermal analysis were applied. Two solid solutions based on a-Cu differing in composition and hardness were found in the structure of the cast Сu–Ni–Mn–Fe alloys. The temperature ranges of solutions’ formation were determined as (1010±10) °С and (890±10) °С, correspondingly. NiMn phase was also formed at (405±15) °С due to precipitation hardening. In the Сu–Ni–Mn–Fe alloys annealed at 500 and 900 °С for 60–750 hours, the volume fraction and size of NiMn precipitates increased with prolonging annealing time and lowering annealing temperature. As iron content was raised up to 2.7 wt. %, the density of NiMn precipitates increased, especially during first 60 hours of annealing at 900 °С. By adding iron, oxidation resistance was improved, but melting temperature and fluidity did not yield any significant change. Hardness of the Сu–Ni–Mn–Fe alloys with higher iron contents increased by 10 НRB on average. However, when test temperature was raised up to 400 °С, tensile strength decreased (by ~1.3 times) and elongation dropped markedly (by ~10 times).

scholarly journals A Study on the Characteristics of Cu–Mn–Dy Alloy Resistive Thin Films

Coatings ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 118 ◽  
Author(s):  
Ho-Yun Lee ◽  
Chi-Wei He ◽  
Ying-Chieh Lee ◽  
Da-Chuan Wu
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Annealing Temperature ◽  
Phase Evolution ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Temperature Coefficient Of Resistance ◽  
X Ray ◽  
Transmission Electronmicroscopy ◽  
Scanning Electron

Cu–Mn–Dy resistive thin films were prepared on glass and Al2O3 substrates, which wasachieved by co-sputtering the Cu–Mn alloy and dysprosium targets. The effects of the addition ofdysprosium on the electrical properties and microstructures of annealed Cu–Mn alloy films wereinvestigated. The composition, microstructural and phase evolution of Cu–Mn–Dy films werecharacterized using field emission scanning electron microscopy, transmission electronmicroscopy and X-ray diffraction. All Cu–Mn–Dy films showed an amorphous structure when theannealing temperature was set at 300 °C. After the annealing temperature was increased to 350 °C,the MnO and Cu phases had a significant presence in the Cu–Mn films. However, no MnO phaseswere observed in Cu–Mn–Dy films at 350 °C. Even Cu–Mn–Dy films annealed at 450 °C showedno MnO phases. This is because Dy addition can suppress MnO formation. Cu–Mn alloy filmswith 40% dysprosium addition that were annealed at 300 °C exhibited a higher resistivity of ∼2100 μΩ·cm with a temperature coefficient of resistance of –85 ppm/°C.

SIZE-INDUCED EFFECTS IN NANOSTRUCTURED NiFe2O4

2010 ◽  
Vol 24 (30) ◽  
pp. 5973-5985
Author(s):  
M. GUNES ◽  
H. GENCER ◽  
T. IZGI ◽  
V. S. KOLAT ◽  
S. ATALAY
Keyword(s):  
Electron Microscopy ◽  
Annealing Temperature ◽  
Structural Parameters ◽  
Hydrothermal Process ◽  
Lattice Parameter ◽  
Effect Of Temperature ◽  
Vibrating Sample Magnetometer ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

NiFe 2 O 4 nanoparticles were successfully prepared by a hydrothermal process, and the effect of temperature on them was studied. The particles were annealed at various temperatures ranging from 413 to 1473 K. Studies were carried out using powder X-ray diffraction, scanning electron microscopy, infrared spectroscopy, differential thermal analysis, thermogravimetric analysis and a vibrating sample magnetometer. The annealing temperature had a significant effect on the magnetic and structural parameters, such as the crystallite size, lattice parameter, magnetization and coercivity.

scholarly journals Double Reinforcement of Al–Fe Intermetallic Composites Fabricated by Friction Stir Processing

Metals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 1002
Author(s):  
Chunping Huang ◽  
Yang Xia ◽  
Chun Xia ◽  
Fencheng Liu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Friction Stir Processing ◽  
Volume Fraction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Friction Stir ◽  
Metallurgical Bond ◽  
Aluminum Alloy Surface ◽  
Scanning Electron

A double reinforced layer on an aluminum alloy surface was produced using friction stir processing (FSP) by adding 34CrNiMo6 powder into Al (AA2024) substrate for better wear resistance and gradient transitions. The microstructures of the composites were analyzed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The phase composition was examined by X-ray diffraction (XRD). The results show that the double reinforced layer of the Al13Fe4 intermetallic compound could be successfully fabricated via FSP. The volume fraction of Al13Fe4 in the double reinforced layer was higher than in the single reinforced layer due to adding 34CrNiMo6 powder and reinforced twice, and the Al13Fe4 particles were dispersed more homogeneously in the double reinforced layer. The interfaces between the double and single reinforced layer had a good metallurgical bond. The microhardness of the double reinforcement layer was significantly increased. Compared with the AA2024 substrate, the microhardness of the double and single reinforced layers increased five- (576 HV) and two-fold (254 HV), respectively.

SiO2ZrO2 Thin Films as Low Temperature NO2 and O3 Sensors

2015 ◽  
Vol 1088 ◽  
pp. 81-85 ◽  
Author(s):  
T.N. Myasoedova ◽  
Victor V. Petrov ◽  
Nina K. Plugotarenko ◽  
Dmitriy V. Sergeenko ◽  
Galina Yalovega ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Scanning Electron Microscopy ◽  
Low Temperature ◽  
Annealing Temperature ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Operating Temperatures ◽  
Scanning Electron

Thin SiO2ZrO2films were prepared, up to 0.2 μm thick, by means of the sol–gel technology and characterized by a Scanning electron microscopy and X-ray diffraction. It is shown the presence of monoclinic, cubic and tetragonal phases of ZrO2in the SiO2matrix. The crystallites sizes depend on the annealing temperature of the film and amount to 35 and 56 nm for the films annealed at 773 and 973 K, respectively. The films resistance is rather sensitive to the presence of NO2and O3impurity in air at lower operating temperatures in the range of 30-60°C.

Effect of Si on As-Cast Microstructure in Quasicrystalline Al-Cu -Fe Alloy

2007 ◽  
Vol 546-549 ◽  
pp. 619-622 ◽  
Author(s):  
Jin Shan Zhang ◽  
Yong Jun Xue ◽  
You Jun Guo ◽  
Chun Xiang Xu ◽  
Wei Liang
Keyword(s):  
Volume Fraction ◽  
Solidification Process ◽  
Quasicrystalline Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Conventional Casting ◽  
Β Phase ◽  
Ω Phase ◽  
Icosahedral Quasicrystalline ◽  
Scanning Electron

Effect of Si on the forming ability of quasicrystalline phase in Al65Cu20Fe15 alloys fabricated under conventional casting conditions has been studied using X-ray diffraction (XRD), optical microscopy (OM), and scanning electron microscopy (SEM). The results show that under the conventional casting conditions, it is found that the addition of certain amount of Si into the Al-Cu-Fe melts can change the formation of Al62.5Cu25Fe12.5 quasicrystals during the solidification process. Compared with Al65Cu20Fe15 alloy, Al64.5Cu20Fe15Si0.5 alloy has smaller volume fraction of β phase solidifying initially, larger volume fraction of the quasicrystal phase generating in the subsequent peritectic reaction, and larger volume fraction of ω phase solidifying finally. Both experimental results and the theory of Hume-Rothery show that addition of Si can promote the formation ability of the icosahedral quasicrystalline Al62.5Cu25Fe12.5 phase in Al-Cu-Fe alloy.

Structural and Morphological Properties of HfxZr1-xO2 Thin Films Prepared by Pechini Route

2010 ◽  
Vol 644 ◽  
pp. 113-116
Author(s):  
L.A. García-Cerda ◽  
Bertha A. Puente Urbina ◽  
M.A. Quevedo-López ◽  
B.E. Gnade ◽  
Leo A. Baldenegro-Perez ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Annealing Temperature ◽  
Precursor Solution ◽  
Dip Coating ◽  
Morphological Properties ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dip Coating Technique ◽  
Scanning Electron

In this study, HfxZr1-xO2 (0 < x < 1) thin films were deposited on silicon wafers using a dip-coating technique and by using a precursor solution prepared by the Pechini route. The effects of annealing temperature on the structure and morphological properties of the proposed films were investigated. HfxZr1-xO2 thin films with 1, 3 and 5 layers were annealed in air for 2 h at 600 and 800 °C and the structural and morphological properties studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). XRD results show that the films have monoclinic and tetragonal structure depending of the Hf and Zr concentration. SEM photographs show that all films consist of nanocrystalline grains with sizes in the range of 6 - 13 nm. The total film thickness is about 90 nm.

Microstructures and Textures During Annealing in Low Carbon Al-Killed Steels with Low Finishing Temperatures and High Coiling Temperatures

2011 ◽  
Vol 194-196 ◽  
pp. 52-55 ◽  
Author(s):  
Bao Cai Wu ◽  
Feng Shi ◽  
Xin Yu Cheng ◽  
Rui Min Lin ◽  
Chun Ming Liu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Optical Microscopy ◽  
Volume Fraction ◽  
Low Carbon ◽  
Coiling Temperature ◽  
X Ray ◽  
Obvious Advantage ◽  
Equiaxed Grain ◽  
Scanning Electron

Microstructures and textures after annealing at 680°C in low carbon Al-killed steels with low finishing temperature and high coiling temperature were investigated by means of optical microscopy (OM), scanning electron microscopy (SEM) and X-Ray Diffractometer (XRD). The results show that higher coiling temperature and lower finishing temperature can both cause the appearance of equiaxed grain and line cementite. The equiaxed grain in 2# steel with higher coiling temperature is the more obvious. Advantage textures are weak in the steels with higher coiling temperature and lower finishing temperature and volume fraction of {111}fiber in 2# steel with higher coiling temperature is only 7.17%, so the stamping property should be worse.

Sol-gel derived Ba(Mg1/3Ta2/3)O3 thin films: Preparation and structure

1997 ◽  
Vol 12 (3) ◽  
pp. 596-599 ◽  
Author(s):  
Ji Zhou ◽  
Qing-Xin Su ◽  
K. M. Moulding ◽  
D. J. Barber
Keyword(s):  
Thin Films ◽  
Annealing Temperature ◽  
Volume Fraction ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Sol Gel Process ◽  
Small Grains

Ba(Mg1/3Ta2/3)O3 thin films were prepared by a sol-gel process involving the reaction of barium isopropoxide, tantalum ethoxide, and magnesium acetate in 2-methoxyethanol and subsequently hydrolysis, spin-coating, and heat treatment. Transmission electron microscopy, x-ray diffraction, and Raman spectroscopy were used for the characterization of the thin films. It was shown that the thin films tend to crystallize with small grains sized below 100 nm. Crystalline phase with cubic (disordered) perovskite structure was formed in the samples annealed at a very low temperature (below 500 °C), and well-crystallized thin films were obtained at 700 °C. Although disordered perovskite is dominant in the thin films annealed below 1000 °C, a low volume fraction of 1 : 2 ordering domains was found in the samples and grows with an increase of annealing temperature.

Fabrication of Ni Sulfides by Thermal Sulfidation

2006 ◽  
Vol 510-511 ◽  
pp. 318-321
Author(s):  
Tae Hyun Nam ◽  
Cheol Am Yu ◽  
Dae Won Jung ◽  
Kwon Koo Cho
Keyword(s):  
Annealing Time ◽  
Annealing Temperature ◽  
Early Stage ◽  
Spherical Particles ◽  
Sulfur Pressure ◽  
X Ray ◽  
Ni Substrate ◽  
Initial Stage ◽  
Fabrication Parameters ◽  
Scanning Electron

The microstructure of Ni sulfides prepared by thermal sulfidation of pure Ni and their dependence of fabrication parameters were investigated by means of scanning electron microscopy and X-ray diffractions. Sulfidation was made by isothermally annealing Ni with the sulfur in vacuum sealed glass ampoules at 673 K for 120 – 600s under the sulfur pressure of 100 and 220 kPa. The sulfide layers formed in the early stage were found to consist of spherical particles smaller than 0.5um, which were grown and agglomerated with increasing annealing temperature. Thickness of sulfides developed on Ni substrate was found to increase with increasing annealing time and sulfur pressure. It was also found that compositions of dominant Ni sulfides changed with varying annealing time. At the initial stage, only Ni3S2 sulfide was formed on pure Ni, which was tightly bonded to Ni substrate. On increasing annealing time, NiS sulfide was formed. On further increasing annealing time, NiS1.97 sulfide was formed, which always coexisted with NiS sulfide. A mechanism for sulfidation of Ni is proposed as follows: 3Ni + 2S Ni3S2, Ni3S2 +S NiS, NiS + S NiS1.97

Doped ZnO Nanowires Obtained by Thermal Annealing

2007 ◽  
Vol 7 (2) ◽  
pp. 700-703 ◽  
Author(s):  
C. X. Shan ◽  
Z. Liu ◽  
C. C. Wong ◽  
S. K. Hark
Keyword(s):  
Thermal Annealing ◽  
Doping Concentration ◽  
Annealing Temperature ◽  
Zno Nanowires ◽  
X Ray Diffraction ◽  
X Ray ◽  
Doped Zno ◽  
Znse Nanowires ◽  
Annealing Method ◽  
Scanning Electron

Doped ZnO nanowires were prepared in a very simple and inexpensive thermal annealing method using ZnSe nanowires as a precursor. As doped, P doped, and As/P codoped ZnO nanowires were obtained in this method. X-ray diffraction shows that the zincblende ZnSe nanowires were converted to doped wurtzite ZnO nanowires. The incorporation of the dopants was confirmed by energy dispersive X-ray spectroscopy. The doping concentration could be adjusted by changing the annealing temperature and duration. Scanning electron microscopy indicated that the morphology of the ZnSe nanowires was essentially retained after the annealing and doping process. Photoluminescence spectroscopy also verified the incorporation of the dopants into the nanowires.

Sign in / Sign up

Export Citation Format

Share Document