Formation of the χ-Phase Precipitate in Co-28Cr-6Mo Alloys with Additional Si and C

2015 ◽  
Vol 46 (9) ◽  
pp. 4342-4350 ◽  
Author(s):  
Kei Sugawara ◽  
Alfirano ◽  
Shingo Mineta ◽  
Kyosuke Ueda ◽  
Takayuki Narushima
Keyword(s):  
Phase Precipitate ◽  
Χ Phase

Analysis of χ phase precipitation in aged 2205 duplex stainless steel

2015 ◽  
Vol 30 (3) ◽  
pp. 591-595 ◽  
Author(s):  
Heping Liu ◽  
Hu’er Sun ◽  
Bin Liu ◽  
Dazhao Li ◽  
Fenger Sun ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Phase Precipitation ◽  
2205 Duplex Stainless Steel ◽  
Χ Phase

Coloring variants of the Re3B type

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Stefan Seidel ◽  
Rainer Pöttgen
Keyword(s):  
Basic Structure ◽  
Crystal Chemical ◽  
Space Group ◽  
Type Space ◽  
Symmetry Reductions ◽  
Phase Precipitate ◽  
Lower Symmetry ◽  
Trigonal Prisms

Abstract The Re3B type, space group Cmcm, has boron-centered trigonal prisms as central building units and is one of the basic structure types with numerous binary and ternary representatives. The coloring of different atoms on the two crystallographically independent rhenium sites leads to a manifold of compounds with different bonding peculiarities that are rather isopointal than isotypic with the prototype. Typical compounds are the S-phase precipitate MgCuAl2, the silicide ScPt2Si or the iodide Th0.5Pb0.5I3 (PuBr3 type). Differences in size or composition might force symmetry reductions. This is discussed for YZn3 (space group Pnma) and the different coloring variants ScRhSi2 and TaNi2P which show different twists of the trigonal prisms. Striking singular representatives with lower symmetry structures are BaThBr6 (Pmma) and NbCo2B (P21/c) which allow different ordering/distortion patterns for the prisms. All these crystal chemical details are discussed on the basis of group subgroup schemes (Bärnighausen trees).

The Metastable Phase Responsible for Hardenig in an Al-Mg Alloy Aged at 473K

2013 ◽  
Vol 748 ◽  
pp. 123-127 ◽  
Author(s):  
Koichiro Fukui ◽  
Ayaka Mori ◽  
Masanori Mitome ◽  
Mahoto Takeda
Keyword(s):  
Precipitation Hardening ◽  
Vickers Microhardness ◽  
Layer Structure ◽  
Metastable Phase ◽  
Mg Alloy ◽  
Stable Phase ◽  
Precipitation Behavior ◽  
Dsc Measurements ◽  
Β Phase ◽  
Phase Precipitate

The present work investigated precipitation behavior in an Al-17at%Mg alloy isothermally aged at 473K, by means of Vickers microhardness tests, DSC measurements and TEM observations. A quantitative analysis of DSC measurements revealed that the metastable β-phase precipitates mainly contribute to precipitation hardening of this alloy aged at 473K. The present STEM-EDX observations confirmed that the metastable β-phase precipitate has a layer structure with a composition similar to the stable phase (Al3Mg2).

scholarly journals Identification of an Al–Ni–O precipitate in combustion-synthesized NiAl

2000 ◽  
Vol 33 (5) ◽  
pp. 1217-1222
Author(s):  
A. Biswas ◽  
Madangopal K. ◽  
J. B. Singh ◽  
S. K. Roy ◽  
S. Banerjee
Keyword(s):  
Room Temperature ◽  
Point Group ◽  
Composition Analysis ◽  
Second Phase ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Phase Precipitate ◽  
Transmission Electron ◽  
Chemical Composition Analysis

The complete identity of a second-phase precipitate detected by transmission electron microscopy in combustion-synthesized NiAl was established. The crystal structure, including the point group, the space group and the lattice parameters, was determined by convergent and selected-area electron diffraction techniques. Energy dispersive X-ray spectroscopy was used for the determination of the chemical composition. Analysis established the phase to be the solid solution of NiO in Al2O3and presented evidence of the hitherto unreported room-temperature solubility.

Structure Refinement of S-Phase Precipitates in Al-Cu-Mg Alloys by Quantitative HRTEM

1999 ◽  
Vol 589 ◽  
Author(s):  
R. Kilaas ◽  
V. Radmilovic ◽  
U. Dahmen
Keyword(s):  
Crystal Structure ◽  
Structural Parameters ◽  
Structure Refinement ◽  
High Resolution Electron Microscopy ◽  
S Phase ◽  
Quantitative Comparison ◽  
Phase Precipitate ◽  
Resolution Electron ◽  
Simulated Images ◽  
Al Matrix

AbstractThe crystal structure of the Al2CuMg S-phase precipitate in an Al matrix has been determined by quantitative high resolution electron microscopy. This work combines techniques of image processing and quantitative comparison between experimental and simulated images with automatic refinement of imaging and structural parameters.

Effects of Thermomechanical Treatment Process on the Microstructure and Properties of 7A04 Aluminum Alloy

2011 ◽  
Vol 335-336 ◽  
pp. 805-808 ◽  
Author(s):  
Shi Xing Zhang ◽  
Hai Hong Wu ◽  
Gang Yi Cai
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Thermomechanical Treatment ◽  
Ageing Time ◽  
Solution Treatment ◽  
Second Phase ◽  
Microstructure And Properties ◽  
Treatment Processes ◽  
Phase Precipitate ◽  
Peak Value

The mechanical properties of a 7A04 aluminum alloy were improved by deformation strengthening and phase transformations strengthening adopting thermomechanical treatment, whose process include solution treatment, deformation treatment and ageing treatment in turn. The paper focuses on the influences of deforming degree and ageing process on microstructure and properties of 7A04 aluminum alloy. The experimental results show that hardness increased with increasing deformation ratio, and the value are greatly higher than that of samples after solution treatment. The results of ageing after deformation show that the hardness enhanced with prolonging the ageing time, which reach the peak value at 16 hours. In addition, the microstructure became more homogeneous and the grain was refined obviously by metallography microscope observation. The second phase precipitate dispersedly to strengthen the alloy. Above all, in order to obtain the better mechanical properties, the optimal thermomechanical treatment processes are solution treatment at 470°C for 2h, deformation with ratio of 40% as well as ageing at 120°C for 16h.

Effects of Thermomechanical Treatment Process on the Microstructure and Properties of Al-Zn-Mg Alloy

2011 ◽  
Vol 239-242 ◽  
pp. 847-850
Author(s):  
Gang Yi Cai ◽  
Yu Yong Yang ◽  
Xiao Hua Li
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Thermomechanical Treatment ◽  
Ageing Time ◽  
Solution Treatment ◽  
Second Phase ◽  
Microstructure And Properties ◽  
Treatment Processes ◽  
Phase Precipitate ◽  
Peak Value

The mechanical properties of Al-Zn-Mg aluminum alloy were improved by deformation strengthening and transformations strengthening adopting thermomechanical treatment, whose process are solution treatment, preageing treatment, deformation treatment and ageing treatment in turn. The paper focuses on the influences of deforming degree and ageing process on microstructure and properties of Al-Zn-Mg aluminum alloy. The experimental results show that hardness increased with increasing deformation ratio, and the value are greatly higher than that of samples after solution treatment. The results of ageing after deformation show that the hardness enhanced with prolonging the ageing time, which reach the peak value at 16 hours. In addition, the microstructure became more homogeneous and the grain was refined obviously by metallography microscope observation. The second phase precipitate dispersedly to strengthen the alloy. Above all, in order to obtain the better mechanical properties, the optimal thermomechanical treatment processes are solution treatment at 470°C for 2h, preageing treatment at 140°C for 24h, deformation with ratio of 40% as well as ageing at 120°C for 16h.

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