scholarly journals Investigation of spectral properties of potassium-aluminum-borate glass with CuCl - CuBr nanocrystals

2021 ◽  
Vol 2103 (1) ◽  
pp. 012172
Author(s):  
A N Babkina ◽  
K S Zyryanova ◽  
Y B Egorova ◽  
A S Kulagina ◽  
R R Gavrilov ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Spectral Properties ◽  
Glass Matrix ◽  
Borate Glass ◽  
Copper Ions ◽  
Aluminum Borate ◽  
Simultaneous Presence ◽  
Exciton Absorption ◽  
Copper Halide ◽  
Treatment Conditions

Abstract Heat treatment conditions effect on the characteristics of exciton absorption and luminescence of CuCl and CuBr nanocrystals in potassium-aluminaborate glass is studied. The size effect of the band edge absorption and luminescence energy is confirmed. The simultaneous presence of copper halide nanocrystals and free monovalent copper ions in the glass matrix is shown. Possible conditions for the formation of mixed CuCl-CuBr crystals are considered.

EPR AND MAGNETIC SUSCEPTIBILITY STUDIES OF COPPER IONS IN THE 2B2O3·Ag2O GLASS MATRIX

2004 ◽  
Vol 18 (20n21) ◽  
pp. 2915-2921 ◽  
Author(s):  
R. CICEO LUCACEL ◽  
I. ARDELEAN
Keyword(s):  
Magnetic Susceptibility ◽  
Glass Matrix ◽  
Magnetic Measurements ◽  
Copper Ions ◽  
Gradual Increase ◽  
Glass Structure ◽  
Ionic Species ◽  
Magnetic Interactions ◽  
Simultaneous Presence ◽  
Distorted Octahedral

Glasses of the x CuO ·(100-x)[2 B 2 O 3· Ag 2 O ] system, with 0<x≤30 mol %, were investigated by means of EPR and magnetic susceptibility measurements. The influence of a gradual increase in CuO content on the glass structure and magnetic interactions that involved copper ions, have been discussed. EPR absorption spectra show Cu 2+ ions in axially distorted octahedral environments. Both EPR and magnetic measurements data pointed out the simultaneous presence in the glasses with x>5 mol % of Cu 2+ and Cu + ionic species. The Curie behavior of magnetic susceptibility indicates the absence of the superexchange interactions in these glasses.

On the defects of enamel coatings

2019 ◽  
pp. 145-150
Author(s):  
T. O. Soshina ◽  
V. R. Mukhamadyarovа
Keyword(s):  
Heat Treatment ◽  
Surface Tension ◽  
Electron Microscope ◽  
Enamel Coating ◽  
Surface Defects ◽  
Linear Expansion ◽  
Corrosion Properties ◽  
Treatment Conditions ◽  
Mechanical And Corrosion Properties ◽  
Coefficient Of Linear Expansion

The defects destroy the integrity of the enamel, and the paper examines the influence of the physical-mechanical and corrosion properties of frits and heat treatment on the defectiveness of the enamel coating. The surface defects were scanned by electron microscope. It has been established that the defectiveness of enamel coatings depends on the melting index, temperature coefficient of linear expansion, surface tension of the frits, and heat treatment conditions. When burning rate of the enamel coating decreases, the fine-meshed structure of the enamel changes, and the size of the defects decreases.

scholarly journals Heat Treatment Evaluation for the Camshafts Production of ADI Low Alloyed with Vanadium

Metals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1036
Author(s):  
Eduardo Colin García ◽  
Alejandro Cruz Ramírez ◽  
Guillermo Reyes Castellanos ◽  
José Federico Chávez Alcalá ◽  
Jaime Téllez Ramírez ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Ductile Iron ◽  
Volume Fraction ◽  
Energy Impact ◽  
Treatment Conditions ◽  
Mold Casting ◽  
Grade 3 ◽  
Good Agreement

Ductile iron camshafts low alloyed with 0.2 and 0.3 wt % vanadium were produced by one of the largest manufacturers of the ductile iron camshafts in México “ARBOMEX S.A de C.V” by a phenolic urethane no-bake sand mold casting method. During functioning, camshafts are subject to bending and torsional stresses, and the lobe surfaces are highly loaded. Thus, high toughness and wear resistance are essential for this component. In this work, two austempering ductile iron heat treatments were evaluated to increase the mechanical properties of tensile strength, hardness, and toughness of the ductile iron camshaft low alloyed with vanadium. The austempering process was held at 265 and 305 °C and austempering times of 30, 60, 90, and 120 min. The volume fraction of high-carbon austenite was determined for the heat treatment conditions by XRD measurements. The ausferritic matrix was determined in 90 min for both austempering temperatures, having a good agreement with the microstructural and hardness evolution as the austempering time increased. The mechanical properties of tensile strength, hardness, and toughness were evaluated from samples obtained from the camshaft and the standard Keel block. The highest mechanical properties were obtained for the austempering heat treatment of 265 °C for 90 min for the ADI containing 0.3 wt % V. The tensile and yield strength were 1200 and 1051 MPa, respectively, while the hardness and the energy impact values were of 47 HRC and 26 J; these values are in the range expected for an ADI grade 3.

Effect of copper incorporation on phase transformation behavior of electroless nickel–phosphorous coating and its effect on the tribological behavior

2020 ◽  
pp. 146442072098160
Author(s):  
Abhijit Biswas ◽  
Suman Kalyan Das ◽  
Prasanta Sahoo
Keyword(s):  
Heat Treatment ◽  
Phase Transformation ◽  
Tribological Behavior ◽  
Electroless Nickel ◽  
Two Phase ◽  
Microstructural Changes ◽  
Treatment Conditions ◽  
Heat Treated ◽  
Higher Temperature ◽  
Effect Of Copper

The microstructural changes of electroless Ni–P–Cu coating at various heat-treatment conditions are investigated to understand its implications on the tribological behavior of the coating. Coatings are heat-treated at temperatures ranging between 200°C and 800 °C and for 1–4 h duration. Ni–P–Cu coatings exhibit two-phase transformations in the temperature range of 350–450 °C and the resulting microstructural changes are found to significantly affect their thermal stability and tribological attributes. Hardness of the coating doubles when heat-treated at 452 °C, due to the formation of harder Ni3P phase and crystalline NiCu. Better friction and wear performance are also noted upon heat treatment of the coating at the phase transformation regime, particularly at 400 °C. Wear mechanism is characterized by a mixed adhesive cum abrasive wear phenomena. Heat treatment at higher temperature (600 °C and above) and longer duration (4 h) results in grain coarsening phenomenon, which negatively influences the hardness and tribological characteristics of the coating. Besides, diffusion of iron from the ferrous substrate as well as greater oxide formation are noticed when the coating is heat-treated at higher temperatures and for longer durations (4 h).

Effect of Heat Treatment Conditions on the Properties of Nanoporous Glasses Activated by Gold Nanoparticles

2021 ◽  
Author(s):  
G. Yu. Shakhgil’dyan ◽  
A. A. Mikhailov ◽  
T. O. Lipat’eva ◽  
K. I. Piyanzina ◽  
E. A. Kolesnikov ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Gold Nanoparticles ◽  
Treatment Conditions

scholarly journals Achievement of High Strength and Ductility in Al–Si–Cu–Mg Alloys by Intermediate Phase Optimization in As-Cast and Heat Treatment Conditions

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 647 ◽  
Author(s):  
Bingrong Zhang ◽  
Lingkun Zhang ◽  
Zhiming Wang ◽  
Anjiang Gao
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Tensile Strength ◽  
Ultimate Tensile Strength ◽  
Intermediate Phase ◽  
High Strength ◽  
Mg Alloys ◽  
Artificial Ageing ◽  
Treatment Conditions ◽  
Eutectic Si

In order to obtain high-strength and high-ductility Al–Si–Cu–Mg alloys, the present research is focused on optimizing the composition of soluble phases, the structure and morphology of insoluble phases, and artificial ageing processes. The results show that the best matches, 0.4 wt% Mg and 1.2 wt% Cu in the Al–9Si alloy, avoided the toxic effect of the blocky Al2Cu on the mechanical properties of the alloy. The addition of 0.6 wt% Zn modified the morphology of eutectic Si from coarse particles to fine fibrous particles and the texture of Fe-rich phases from acicular β-Fe to blocky π-Fe in the Al–9Si–1.2Cu–0.4Mg-based alloy. With the optimization of the heat treatment parameters, the spherical eutectic Si and the fully fused β-Fe dramatically improved the ultimate tensile strength and elongation to fracture. Compared with the Al–9Si–1.2Cu–0.4Mg-based alloy, the 0.6 wt% Zn modified alloy not only increased the ultimate tensile strength and elongation to fracture of peak ageing but also reduced the time of peak ageing. The following improved combination of higher tensile strength and higher elongation was achieved for 0.6 wt% Zn modified alloy by double-stage ageing: 100 °C × 3 h + 180 °C × 7 h, with mechanical properties of ultimate tensile strength (UTS) of ~371 MPa, yield strength (YS) of ~291 MPa, and elongation to fracture (E%) of ~5.6%.

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