Change in the phase composition of corundum-mullite-cordierite refractories under heat treatment

1997 ◽  
Vol 38 (9-10) ◽  
pp. 383-387
Author(s):  
S. M. Logvinkov ◽  
G. D. Semchenko ◽  
D. A. Kobyzeva
Keyword(s):  
Heat Treatment ◽  
Phase Composition

A Contribution to the Structure Characteristics and Phase Composition of Vanadium-Phosphorus Catalysts Prepared from the VOPO4.xH2O.yH3PO4 Precursor

1992 ◽  
Vol 57 (12) ◽  
pp. 2475-2480 ◽  
Author(s):  
Milan Brutovský ◽  
Štefan Gerej ◽  
Ján Novák ◽  
Lucia Ferdinandyová
Keyword(s):  
Heat Treatment ◽  
Phase Composition ◽  
Ir Spectra ◽  
Metal Cations ◽  
Preparation Procedure ◽  
Final Temperature ◽  
Structure Characteristics ◽  
Heat Treatment Regime ◽  
Condensed Phosphates ◽  
Defective Crystals

Catalysts were prepared from VOPO4.xH2O.yH3PO4 (x = 0.3-2, y = 0.2-0.85) by reduction with SO2 up to a final temperature of 750-800 °C, and activated in a reaction mixture of 1.0-1.4% butane in air up to 500 °C. The structure characteristics and phase composition of the catalysts were found to be affected by the preparation procedure and heat treatment regime. Their diffraction lines and IR spectra revealed that the catalysts from larger and less defective crystals than catalysts which were obtained from the VOHPO4.xH2O.yH3PO4 precursor and activated in the reaction mixture at temperatures up to 500 °C. In the catalysts prepared by the above procedure, the tendency to the formation of phases of higher-condensed phosphates, in particular VO(PO3)2 or even V(PO3)3, increases with increasing n(P):n(V) ratio and is then more pronounced than with vanadium-phosphorus catalysts prepared by other procedures. The tendency to the formation of the catalytically less active condensed phosphates is partly suppressed by the embedding of modifying metal cations (Fe or Cu in this case).

Microstructure and Mechanical Properties of Ti-6Al-4V Manufactured by SLM

2015 ◽  
Vol 651-653 ◽  
pp. 677-682 ◽  
Author(s):  
Anatoliy Popovich ◽  
Vadim Sufiiarov ◽  
Evgenii Borisov ◽  
Igor Polozov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Mechanical Behavior ◽  
Ductile Fracture ◽  
Elevated Temperatures ◽  
Initial Material ◽  
Laser Melting ◽  
Microstructure And Mechanical Properties ◽  
Before And After

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

Investigation of Microstructure and Property of Fe3Al/Al2O3 Composites

2010 ◽  
Vol 150-151 ◽  
pp. 1409-1412 ◽  
Author(s):  
Tao Jiang
Keyword(s):  
Heat Treatment ◽  
Phase Composition ◽  
Mechanical Alloying ◽  
Sintering Process ◽  
Composite Powders ◽  
Al2o3 Composite ◽  
Al2o3 Phase ◽  
The Mean ◽  
Xrd Patterns ◽  
Al2o3 Matrix

The Fe3Al/Al2O3 composites were fabricated by pressureless sintering process. The Fe3Al intermetallics compounds powders were fabricated by mechanical alloying and heat treatment, then the Fe3Al powders and Al2O3 powders were mixed and the Fe3Al/Al2O3 composite powders were prepared, so the Fe3Al/Al2O3 composites were fabricated by sintering process at 1700oC for 2h. The phase composition and microstructure of Fe3Al intermetallics compounds powders produced by mechanical alloying and heat treatment were investigated. The phase composition, microstructure and mechanical properties of the Fe3Al/Al2O3 composites sintered bulks were investigated. The XRD patterns results showed that there existed Fe3Al phase and Al2O3 phase in the sintered composites. The Fe3Al/Al2O3 composites sintered bulks exhibited the homogenous and compact microstructure, the Fe3Al particles were homogenously distributed in the Al2O3 matrix, the mean particles size of Fe3Al intermetallics was about 3-5μm. The Fe3Al/Al2O3 composites exhibited more homogenous and compact microstructure with the increase of Fe3Al content in the Al2O3 matrix. The density and relative density of the Fe3Al/Al2O3 composites increased gradually with the increase of Fe3Al content. The fracture strength and fracture toughness of the Fe3Al/Al2O3 composites increased gradually with the increase of Fe3Al content. The elastic modulus and hardness (HRA) of the Fe3Al/Al2O3 composites decreased gradually with the increase of Fe3Al content.

Heat treatememt effect on microstructure and mechanical properties of precipitation hardening elinvar alloy

2021 ◽  
pp. 68-73
Author(s):  
G.V. Shlyakhova ◽  
◽  
A.V. Bochkareva ◽  
M.V. Nadezhkin ◽  
◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Structural Analysis ◽  
Thermal Treatment ◽  
Precipitation Hardening ◽  
Physical And Mechanical Properties ◽  
Alloy Structure ◽  
Treatment Mode ◽  
Elinvar Alloy

This study presents experimental results of structural analysis, such as phase composition, grains size assessment, strength and hardness of Ni-SPAN-C alloy 902 after various heat treatment modes (hardening and aging for stress relaxation). A thermal treatment mode has been selected to obtain higher physical and mechanical properties of the elinvar alloy. It is shown that the improvement of the alloy structure in thermal treatment occurs due to the thermic stresses, as well as the formation and dissolution of intermetallides.

The effect of phase transformations in the process of electrom-beam 3D-printing and post-built heat treatment on the peculiarities of plastic deformation and fracture of high nitrogen Cr-Mn steel

2021 ◽  
pp. 10-17
Author(s):  
E.G. Astafurova ◽  
◽  
K.A. Reunova ◽  
S.V. Astafurov ◽  
M.Yu. Panchenko ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Plastic Deformation ◽  
Electron Beam ◽  
Phase Composition ◽  
Additive Manufacturing ◽  
3D Printing ◽  
Raw Material ◽  
High Nitrogen ◽  
Two Phase ◽  
Deformation And Fracture

We investigated the phase composition, plastic deformation and fracture micromechanisms of Fe-(25-26)Cr-(5-12)Mn-0.15C-0.55N (wt. %) high-nitrogen chromium-manganese steel. Obtained by the method of electron-beam 3D-printing (additive manufacturing) and subjected to a heat treatment (at a temperature of 1150°C following by quenching). To establish the effect of the electron-beam 3D-printing process on the phase composition, microstructure and mechanical properties of high-nitrogen steel, a comparison was made with the data for Fe-21Cr-22Mn-0.15C-0.53N austenitic steel (wt. %) obtained by traditional methods (casting and heat treatment) and used as a raw material for additive manufacturing. It was experimentally established that in the specimens obtained by additive manufacturing method, depletion of the steel composition by manganese in the electron-beam 3D-printing and post-built heat treatment contributes to the formation of a macroscopically and microscopically inhomogeneous two-phase structure. In the steel specimens, macroscopic regions of irregular shape with large ferrite grains or a two-phase austenite-ferrite structure (microscopic inhomogeneity) were observed. Despite the change in the concentration of the basic elements (chromium and manganese) in additive manufacturing, a high concentration of interstitial atoms (nitrogen and carbon) remains in steel. This contributes to the macroscopically heterogeneous distribution of interstitial atoms in the specimens - the formation of a supersaturated interstitial solid solution in the austenitic regions due to the low solubility of nitrogen and carbon in the ferrite regions. This inhomogeneous heterophase (ferrite-austenite) structure has high strength properties, good ductility and work hardening, which are close to those of the specimens of the initial high-nitrogen austenitic steel used as the raw material for additive manufacturing.

Effect of heat treatment on the structure, phase composition, and mechanical properties of VN-10 alloy

1993 ◽  
Vol 29 (1) ◽  
pp. 56-60 ◽  
Author(s):  
O. I. Eliseeva ◽  
V. I. Kalyandruk ◽  
A. A. Denisova ◽  
V. V. Shirokov
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Structure Phase

Regularities of the formation of the phase composition, structure and properties of the БрНХК 2.5-0.7-0.6 alloy during thermal and aerothermoacoustic treatments

2021 ◽  
pp. 71-75
Author(s):  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Phase Composition ◽  
Aging Treatment ◽  
Structure And Properties ◽  
Additional Increase ◽  
Composition Structure ◽  
Aerothermoacoustic Treatment

The influence of thermal and aerothermoacoustic treatments on the structure and mechanical properties of БрНХК bronze is considered. An increase in the strength and elasticity of the alloy is established by optimizing the thermal and aerothermoacoustic modes. The influence of the pre-aging treatment, the aging and aerothermoacoustic modes on the structure, the possibility of an additional increase in the mechanical properties of wire from БрНХК after aerothermoacoustic treatment are shown. Keywords: bronze, heat treatment, aerothermoacoustic treatment, microstructure, mechanical properties. [email protected]

Micromorphology and Characterization of V2O3 Nanoparticles Produced by the Liquid Phase Reduction-Heat Treatment

2019 ◽  
Vol 944 ◽  
pp. 650-656
Author(s):  
Ming Rui Zhang ◽  
Yuan Qin ◽  
Dao Zhang ◽  
Guang Yuan Wang ◽  
Sen Yang
Keyword(s):  
Heat Treatment ◽  
Phase Composition ◽  
Liquid Phase ◽  
Thermal Treatment ◽  
Oxalic Acid ◽  
Structure And Morphology ◽  
Phase Reduction ◽  
Novel Method ◽  
Composition Structure

The liquid phase reduction-heat treatment has been used to prepare V2O3nanoparticles in this paper. It is a novel method that the precursor was developed by Oxalic acid dehydrate (H2C2O4·2H2O) reduction of V2O5powder in anhydrous ethanol. V2O3nanoparticles were successfully obtained by thermal treatment of the precursor. The phase, composition, structure, and morphology of the as-obtained samples were verified by XRD, XPS, SEM and TEM measurements. Meanwhile, the possible formation mechanism of V2O3in the heat-treatment is briefly discussed by analyzing the DSC.

scholarly journals The Phase Composition and Mechanical Properties of the Novel Precipitation-Strengthening Al-Cu-Er-Mn-Zr Alloy

2020 ◽  
Vol 10 (15) ◽  
pp. 5345
Author(s):  
Sayed Amer ◽  
Olga Yakovtseva ◽  
Irina Loginova ◽  
Svetlana Medvedeva ◽  
Alexey Prosviryakov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Phase Composition ◽  
Ultimate Tensile Strength ◽  
Cast Alloy ◽  
Precipitation Strengthening ◽  
The Novel ◽  
Annealed Alloy ◽  
Zr Alloy

The microstructure, phase composition, and mechanical properties during heat treatment and rolling of the novel Al-5.0Cu-3.2Er-0.9Mn-0.3Zr alloy were evaluated. A new quaternary (Al,Cu,Mn,Er) phase with possible composition Al25Cu4Mn2Er was found in the as-cast alloy. Al20Cu2Mn3 and Al3(Zr,Er) phases were nucleated during homogenization, and θ″(Al2Cu) precipitates were nucleated during aging. The metastable disc shaped θ″(Al2Cu) precipitates with a thickness of 5 nm and diameter of 100–200 nm were nucleated mostly on the Al3(Zr,Er) phase precipitates with a diameter of 35 nm. The hardness Vickers (HV) peak was found after the annealing of a rolled alloy at 150 °C due to strengthening by θ″(A2Cu) precipitates, which have a larger effect in materials hardness than do the softening processes. The novel Al-Cu-Er-Mn-Zr alloy has a yield strength (YS) of 320–332 MPa, an ultimate tensile strength (UTS) of 360–370 MPa, and an El. of 3.2–4.0% in the annealed alloy after rolling condition.

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