https://www.elibrary.ru/title_about_new.asp?i
1605-8119
Materials physics and mechanics
11
1
2011
1-93
RAR
RUS
1-8
Chonbuk National University
Lim
Republic of Korea
Udayana University
Suardana
Bali, Indonesia
Chonbuk National University
Piao
Republic of Korea
Mechanical Properties of HEMP Fibers and HEMP/PP Composites: Effects of Chemical Surface Treatment
The effects of chemical surface treatment on the hemp fibers and mechanical properties of hemp fiber composites were investigated. After chemical treatment of the fibers, the density and weight loss were measured. The surface morphologies of fibers were observed using SEM, and FT-IR was utilized to characterize the chemically modified fibers. Among the tested samples, the 4 wt.% NaOH-treated fiber composites demonstrated the best mechanical properties. The fracture surfaces of the composites were also observed by SEM.
HEMP Fibers
HEMP/PP Composites
Chemical Surface Treatment
https://mpm.spbstu.ru/article/2011.16.1/
MPM_11_1_P01.pdf
RAR
RUS
9-16
Government College of Technology
Ganesan
Tamilnadu, India
Angel College of Engineering & Technology
Selvakumari
Tamilnadu, India
Government Arts College
Emerson
Tamilnadu, India
Magnetic Properties of Urea Doped Nanocrystalline FePtP Films
This paper reports a unique approach to the fabrication of FePtP films by electroplating technique which is especially interesting due to its low cost, high throughput and high quality of deposit. Effect of concentration of urea in the presence of sodium hyphophosphite was studied. Vibration sample magnetometric studies indicate that has favourable impact on the magnetic properties of these films. Elemental composition of the molecules was studied using energy dispersive X-ray spectroscopy. The result shows that the phosphorous content was found to be less than 10%. Morphology and structural properties were carried out using scanning electron microscopy and X-ray diffractometry. Reasons for variation in magnetic properties and structural characteristics are discussed. Mechanical properties such as residual stress, hardness and adhesion of the films were also studied.
FePtP
Nanocrystalline Films
Magnetic Properties
https://mpm.spbstu.ru/article/2011.16.2/
MPM_11_1_P02.pdf
RAR
RUS
17-22
Mata Gujri College
Singh
India
Punjabi University
Mudahar
India
Thind
Canada
Govt. MSSS Civil Lines
Singh
India
Punjabi University
Singh
India
Optical Characterization of Fly Ash as a Glass Modifier in Potassium Borate Glasses
We have prepared alkali borate glass with fly ash as a network modifier (upto 5 mole %). Results have been compared with binary potassium borate glass and potassium borate glass with lead oxide as a modifier having same content as that of fly ash. Structural changes induced by addition of fly ash have been investigated by UV-VIS and FTIR spectroscopy, XRD and density measurements. This work can lead to future application of utilization and characterization of fly ash in glass forming materials.
Potassium Borate Glasses
UV-VIS
FTIR spectroscopy
XRD
Density measurements
https://mpm.spbstu.ru/article/2011.16.3/
MPM_11_1_P03.pdf
RAR
RUS
23-59
Institute of Problems of Mechanical Engineering RAS
Zhigacheva
St.Petersburg, Russia
The CRISM “Prometey”
Barakhtin
St.Petersburg, Russia
Institute of Problems of Mechanical Engineering RAS
Meshcheryakov
Yu.I.
St.Petersburg, Russia
Institute of Problems of Mechanical Engineering RAS
Divakov
St.Petersburg, Russia
Threshold Regimes and Micromechanisms of Dynamic Straining
Two conditions for resonance interaction of loading stress pulse and polarized dislocation structure are found: (1) equality of space period of the dislocation structure and space period of shock front, (2) equality of local strain rate at the mesoscale and macroscopic strain rate. Shock tests of D16 aluminum alloy within impact velocity range of 30-450 m/s have shown that maximum dynamic strength is realized when both above conditions for resonance interaction are fulfilled simultaneously, which occurs at the impact velocity of 382m/s. The resonance interaction results in formation of deformation structures of mesoscopic scale revealed with metallographic techniques and X-ray analysis of post shocked specimens.
particle velocity dispersion; velocity defect; meso-macro energy exchange; dynamic re-crystallization; dynamic strength
https://mpm.spbstu.ru/article/2011.16.4/
MPM_11_1_P04.pdf
RAR
RUS
60-67
Guru Nanak Dev University
Singh
India
Guru Nanak Dev University
Kaur
India
Guru Nanak Dev University
Singh
India
Guru Nanak Dev University
Kaur
India
Electrical and Dielectric Characteristics of Annealed Muscovite Ruby Mica
The electrical and dielectric response of muscovite ruby mica has been investigated by measuring various parameters (Impedance, Impedance phase angle, Susceptance, Admittance, Dissipation factor or tanδ, Quality factor, Static capacitance in series-equivalent circuit mode, Static capacitance in parallel-equivalent circuit mode) as a function of frequency (range between ~10 MHz to 120 MHz) at different annealing temperature (range between room temperature to 1050 o C). The present work reveals the influence of thermal treatment on the electrical/dielectric characteristics of muscovite ruby mica. The high temperature annealed mica shows approximately 72% low quality factor as compared to the unannealed mica. This paper will be helpful for the better utilization of muscovite in various high temperature and frequency equipments.
annealed mica; electrical and dielectric characteristics
https://mpm.spbstu.ru/article/2011.16.5/
MPM_11_1_P05.pdf
RAR
RUS
68-75
Institute Silicate Chemistry of Russian Academy of Science
Solovyeva
E.N.
St.Petersburg, Russia
Scientific and Technical Center “Glass and Ceramics”
Archakov
St.Petersburg, Russia
Scientific and Technical Center “Glass and Ceramics”
Borisova
St.Petersburg, Russia
Federal State Unitary Enterprise Smolensk Production Association “ANALITPRIBOR”,
Shorokhov
Smolensk, Russia
Institute Silicate Chemistry of Russian Academy of Science
Konakov
V.G.
St.Petersburg, Russia
Scientific and Technical Center “Glass and Ceramics”
Golubev
St.Petersburg, Russia
Agglomerate Size in Precursors and Mechanical Strength of Solid Elestrolytes Based on Y2O3-ZrO2 System
Precursor powders with the average agglomerate size of 40-1200 nm were synthesized using the reverse co-precipitation version of sol-gel method. The dependence of the mechanical strength of Y-Zr ceramics on the precursor dispersity has been studied using BET, laser PSD (particle size distribution), TEM, XRD, and DSC methods.
Y-Zr ceramics; precursor powders; reverse precipitation sol-gel synthesis; mechanical strength of ceramics
https://mpm.spbstu.ru/article/2011.16.6/
MPM_11_1_P06.pdf
RAR
RUS
76-93
Institute of Problems of Mechanical Engineering RAS
I.A. Ovid’ko
И.А.
St.Petersburg, Russia
113263
6701854079
0000-0001-9909-2950
Institute of Problems of Mechanical Engineering RAS
Sheinerman
Alexander
St.Petersburg, Russia
Effect of Hydrogen on Strength of Nanoceramics
The effects of hydrogen on strength of nanoceramics are theoretically studied. Within the approach suggested, the effects of hydrogen on the principle fracture processes that control strength - nanocrack generation and the growth of pre-existent cracks - in deformed nanoceramics containing hydrogen are analyzed. The conditions at which nanocrack growth near disclination dipoles is energetically favored in nanoceramics α-Al2O3 (corund) and 3C-SiC (the cubic phase of silicon carbide) are revealed, and the equilibrium lengths of such nanocracks are calculated. It is shown that the equilibrium lengths of nanocracks increase in the presence of hydrogen and can be close to the grain size. As a consequence, such nanocracks can merge resulting in brittle fracture of nanoceramics. Also, the effects of dislocations with large Burgers vectors, which form in the course of grain boundary sliding, and hydrogen impurities on the propagation of pre-existent cracks in nanoceramics are analysed. It is demonstrated that grain boundary sliding leads to an increase of the values of the critical stress intensity factor by 10 to 30 percent, whereas, in contrast, the presence of hydrogen can reduce these values by a factor of 1.5 and more. Thus, it is demonstrated that hydrogen promotes the embrittlement of nanoceramics.
nanoceramics
cracks
hydrogen embrittlement
https://mpm.spbstu.ru/article/2011.16.7/
MPM_11_1_P07.pdf