- TITLE:
AN INVESTIGATION ABOUT THE EFFECT OF LOAD ON DRY SLIDING WEAR PERFORMANCE OF AA7075-T6
- AUTHOR(S):
M. Ceviz, C. Misirli,S. S. Karabeyoglu
- ABSTRACT:
Aluminum alloys are taking the place of conventional steel and other alloys owing to their high
mechanical and corrosion properties. The extensive application of AA7075-T6 in the aerospace,
automotive and structure industries is due to its high strength-to-weight ratio, low corrosion
potential and high machining properties and therefor requires detailed investigation. Frictional
behavior of AA7075-T6 against ball for low loads (3N, 5N and 7N) was investigated to
characterize the worn surface in terms of wear rate and coefficient of friction (COF) using a pin-on-
disc tribometer. Microstructural composition was depicted with optical microscope (OM). Wear rate
and COF values were investigated accordance with different low test loads. A detailed tribological
characterization was carried out using scanning electron microscope (SEM) and energy dispersive
X-ray spectroscopy (EDX) and wear track profiles were observed. In the AA7075-T6 alloy present
phases were determined using X-ray diffractometer (XRD) analysis. Morphological
characterizations were accomplished by SEM and wear mechanisms were examined.32 OAl
- PAGES:
51-
- TITLE:
INFLUENCE OF THE PRESSING FORCE ON THE MECHANICAL CHARACTERISTICS OF AN IRON MATRIX OF WATER- DISPERSED POWDERS ALLOYED WITH NICKEL
- AUTHOR(S):
I. Miteva, I. Mitev
- ABSTRACT:
In this publication the influence of the pressing force on the mechanical characteristics of
sintered materials based on water-dispersed iron powders alloyed with nickel is studied. An iron
matrix based on water-dispersed powders type AHC 100.29, to which up to 4% nickel was added,
was studied. After pressing with a force of 300 ÷ 800 MPa, they were sintered at a temperature of
1150ºC for 1h in a dissociated ammonia medium. Experiments were performed to determine tensile
strength, yield strength, elongation, Young's modulus, hardness, impact energy and dimensional
changes. In determining the mechanical characteristics in order to prevent the influence of porosity,
five measurements were made for each type of samples, and in the graphical interpretation of the
results the arithmetic mean values were used.
- PAGES:
47-
- TITLE:
STUDY OF THE KINEMATICS OF THE MOVEMENT OF SOLID INCLUSION IN PLASTIC FLOW
- AUTHOR(S):
V. Titov, N. Zlochevska, A. Lavrinenkov, V. Skrypnikova, D. Korotin
- ABSTRACT:
The conditions of interaction of a solid-reinforcing inclusion with a metal matrix of a dispersed-
reinforced composite material in the focus of deformations during isothermal pressing are
considered. As a result of numerical modeling, the mechanism of reorientation in the direction of
metal flow of solid reinforcing inclusions is substantiated. It is shown that the mechanism of rotation
of the inclusion in the direction of flow of the metal depends on the gradient of the velocities of the
material particles of the matrix. It is shown that the use of back pressure improves the interaction
conditions at the boundary surface of the inclusion and the matrix, reduces the likelihood of
microcracks, and the process in hot plastic deformation creates conditions for "healing" of existing
microdamages.
- PAGES:
42-
- TITLE:
INCREASING THE RESOURCE OF PLASTICITY OF ALUMINUM ALLOY AMG6 BY THERMOMECHANICAL TREATMENT UNDER UNIAXIAL TENSION CONDITIONS
- AUTHOR(S):
V. A. Titov, V. O. Koreva
- ABSTRACT:
Increasing of the plasticity resource by thermomechanical treatment by using intermediate
annealing in the deformation process is investigated. Tensile tests were performed on the specimens.
The elongation of the plasticity of the aluminum alloy AMg6 by thermomechanical treatment during
tensile tests was determined. It is established that the decrease in the efficiency of intermediate
annealing at individual transitions is explained by the accumulation of metal damage during
previous deformation. The assessment shows that intermediate annealing provides an increase in the
resource of plasticity of the material in 1.5… 1.6 times.
- PAGES:
39-
- TITLE:
POSSIBILITIES OF INCREASING THE PRODUCTIVITY OF THE ULTRASONIC ATOMISER
- AUTHOR(S):
O. Luhovskyi, A. Shulha, A. Zilinskyi, I. Gryshko, A. Movchanuk
- ABSTRACT:
Ultrasonic thin film atomisation produces a quality monodisperse aerosol with a dispersity of up
to 5 ... 30 μm at an ultrasonic frequency of 22 ... 66 kHz. Obtained monodisperse aerosol can be used
in many technological processes, especially when the possibility of using other methods of
atomization is limited by the properties of the liquid. Such technological processes are widely used in
mechanical engineering, chemical industry, medicine and agriculture as part of mechatronic
automation systems and many other industries.
- PAGES:
32-
