A resource- and energy-saving technology for using foam paints to decorate manufactured glass articles was developed. The optimal parameters for firing the coating by a plasma-forming argon-gas flow ...were determined. The effect of sodium liquid glass on the quality of a decorative coating was investigated.
New Trends in Glass Matting Technologies Bessmertnyi, V. S.; Zdorenko, N. M.; Kochurin, D. V. ...
Glass and ceramics,
03/2023, Volume:
79, Issue:
11-12
Journal Article
Peer reviewed
Contemporaneous trends in the development of technologies for matting glass and products from matted glass are considered. An efficient glass matting technology has been developed using an ...alternative source of energy—low-temperature plasma. It is demonstrated that a high-quality matt surface of the type ‘frosty matting’ is formed by using iron powders with dispersivity 160 and 450 µm. The microstructure of the matted surface was investigated. Theoretical aspects of matting glass are considered. The technological parameters of matting are determined and the developed technology is shown to be economically efficient.
The work is devoted to the study of the effect of multi-step heat treatment on the formation of the microstructure of the alloy of Al–Mg–Si series, alloyed with scandium and zirconium at the ratio of ...Mg/Si = 0.3. For this purpose, the base AlMgSi alloy, containing no scandium and zirconium, as well as its modification AlMgSiScZr with additions of these elements were cast. Multi-step heat treatment of AlMgSiScZr alloy consisted of four steps of annealing: at 550°C for 8 h + at 440°C for 8 h + at 500°C for 0.5 h + at 180°C for 5 h. For AlMgSi alloy, it included two steps: at 550°C for 8 h + at 180°C for 5 h. The microstructure of AlMgSiScZr alloy was studied in the cast state, as well as after each step of heat treatment by scanning and transmission electron microscopy, while AlMgSi alloy was studied in the cast state and after the final heat treatment. After each step of heat treatment, the microhardness of the studied alloys was measured. It was found that during cooling of the ingot, in the alloys under consideration coarse intermetallics of Fe
2
Mg
7
Si
10
Al
18
type were formed, which partially were dissolved during subsequent heat treatment. At the same time, in the alloy with scandium and zirconium additives, particles that can be attributed either to (AlSi)
3
ScZr or to the τ (phase) of AlSc
2
Si
2
are present at the intergranular boundaries. No traces of intermittent decomposition of the scandium supersaturated solid solution during cooling of the ingot were found. Heat treatment at 550°C for 8 h + at 440°C for 8 h leads to the appearance of a phase that can be both AlSc
2
Si
2
and Al
5
SiZr
2
, while no (AlSi)
3
ScZr nanoparticles are formed. Heating at 500°C for 30 min enables complete dissolution of the magnesium-containing particles. At the final step, β" (Mg
5
Si
6
) particles are formed in the investigated alloys, while scandium has no significant effect on their formation.
Abstract
One of the most important issues of maintainability of engineering products is an experimental evaluation of quantitative maintainability indices. It is necessary to plan maintenance and ...repair tests of products to obtain estimates. The analytical dependencies to determine amount of check and determinative tests and value of specified maintenance time for the cases of normal and exponential distribution laws of maintainability indices have been derived in the article. The numerical examples of calculation of amount of tests and evaluation of maintainability indices of engineering products have been represented.
The excess internal energies Δ
U
Q
and excess entropies
of ten metallic glasses with respect to their parent crystalline states are determined from calorimetric studies. The elastic energy Δ
U
el
of ...the subsystem of interstitial defects responsible for relaxation phenomena in metallic glasses according to interstitialcy theory is calculated within this theory using the measured high-frequency shear modulus. It is established that the quantities Δ
U
Q
and Δ
U
el
coincide with each other within an accuracy of no less than 10–15%. It is concluded that the excess internal energy and excess entropy of metallic glasses are due primarily to the elastic energy of the subsystem of interstitial defects. The dissipation of this energy into heat under heating reduces Δ
U
Q
and Δ
S
Q
to zero because of the complete crystallization. The entropy per defect is estimated from calorimetric data as
S
d
≈ (20–30)
k
B
, which is characteristic of interstitial defects.
When designing steam-generating devices, it is necessary to consider the issue of determining the limits of their stable operation. Such stable operation limits can be determined by testing a model ...that reflects the main design features of a full-scale steam generator. For this purpose, JSC OKBM Afrikantov has developed and tested a steam generator model. The results obtained in the tests for determining the limits of hydrodynamic stability can be used to determine the permitted range of operating loads for steam generators.
We discuss the design, development, and evaluation of an Orbitrap/time-of-flight (TOF) mass spectrometry (MS)-based instrument with integrated UV photodissociation (UVPD) and time/mass-to-charge ...ratio (m/z)-resolved imaging for the comprehensive study of the higher-order molecular structure of macromolecular assemblies (MMAs). A bespoke TOF analyzer has been coupled to the higher-energy collisional dissociation cell of an ultrahigh mass range hybrid quadrupole-Orbitrap MS. A 193 nm excimer laser was employed to photofragment MMA ions. A combination of microchannel plates (MCPs)-Timepix (TPX) quad and MCPs-phosphor screen-TPX3CAM assemblies have been used as axial and orthogonal imaging detectors, respectively. The instrument can operate in four different modes, where the UVPD-generated fragment ions from the native MMA ions can be measured with high-mass resolution or imaged in a mass-resolved manner to reveal the relative positions of the UVPD fragments postdissociation. This information is intended to be utilized for retrieving higher-order molecular structural details that include the conformation, subunit stoichiometry, and molecular interactions as well as to understand the dissociation dynamics of the MMAs in the gas phase.
Special features of structure formation in steel 30Kh2GSN2BM under continuous cooling from the temperature of complete austenitization and under an isothermal hold in the temperature range of ...bainitic transformation are studied. Metallographic and x-ray diffraction phase analysis are performed and tensile and impact bending tests of specimens are conducted. The data of the dilatometric and metallographic studies are used to plot a thermokinetic diagram of transformation of supercooled austenite. The laws of variation of mechanical properties of the steel after oil quenching and tempering and after normalizing in air and different variants of isothermal quenching are determined.
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