scholarly journals Influence of heat treatment on thermokinetic EMF during reverse phase transition in titanium nickelide

2020 ◽  
Vol 65 (4) ◽  
pp. 413-421
Author(s):  
O. A. Petrova-Burkina ◽  
V. V. Rubanik, Jr. ◽  
V. V. Rubanik ◽  
T. V. Gamzeleva
Keyword(s):  
Mechanical Properties ◽  
Phase Transition ◽  
Heat Treatment ◽  
Oxide Layer ◽  
Thermal Cycle ◽  
Titanium Nickelide ◽  
Physical And Mechanical Properties ◽  
Sample Surface ◽  
Reverse Phase ◽  
X Ray

The effect of duration and annealing temperature in the range of 400–800 °C on the thermokinetic EMF value in titanium nickelide, the composition of which is close to the equi-atomic one, at a reverse phase transition was investigated. Thermokinetic EMF was measured directly using a digital millivoltmeter MNIPI V7-72. The phase and elemental composition of the alloy and the kinetics of thermoelastic phase transformations have been checked by X-ray diffraction and calorimetric studies, and X-ray microanalysis. Annealing at temperatures of 500 and 800 °C leads to an increase in the thermokinetic EMF value from 0.22 to 0.25 mV. Removal of the oxide layer from the sample surface annealed at 700 °C for 0.5 h leads to an increase in the thermokinetic EMF value from 0.22 to 0.26 mV for the 1-st thermal cycle. It was found that thermal cycling causes a decrease in the thermokinetic EMF values down to 0.98 mV for the 20th thermal cycle for the samples without an oxide layer and to 0.3 mV for the samples with an oxide layer, respectively. With the increase in annealing time up to 20 h at 700 °C, the decrease in the thermokinetic emf value to 0.16 mV was observed. The thermokinetic EMF value after heat treatment is associated with changes in the physical and mechanical properties of the alloy and characterized by a shift of the characteristic temperatures of the phase transition. The research results are important for understanding the physics of thermoelectric phenomena in shape memory alloys during nonstationary heating and can be used both to control the homogeneity of their physical and mechanical properties and to design smart actuators and sensors, mechanisms of control systems.

Physical and Mechanical Properties of Cement Paste Were Used Partially with Fly Ash and Kaolin Waste

2017 ◽  
Vol 866 ◽  
pp. 199-203
Author(s):  
Chidchanok Chainej ◽  
Suparut Narksitipan ◽  
Nittaya Jaitanong
Keyword(s):  
Mechanical Properties ◽  
Fly Ash ◽  
Room Temperature ◽  
Physical And Mechanical Properties ◽  
Partial Replacement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Lime Water ◽  
Diffraction Patterns ◽  
Iron Mold

The aims of this research were study the microstructures and mechanical properties for partial replacement of cement with Fly ash (FA) and kaolin waste (KW). Ordinary Portland cement were partially replaced with FA and KW in the range of 25-35% and 10-25% by weight of cement powder. The kaolin waste was ground for 180 minutes before using. The specimen was packing into an iron mold which sample size of 5×5×5 cm3. Then, the specimens were kept at room temperature for 24 hours and were moist cured in the incubation lime water bath at age of 3 days. After that the specimens were dry cured with plastic wrap at age of 3, 7, 14 and 28 days. After that the compounds were examined by x-ray diffraction patterns (XRD) and the microstructures were examined by scanning electron microscopy (SEM). The compressive strength was then investigated.

scholarly journals Features of the hydration process of the modified blended cement for fiber cement panels

2018 ◽  
Vol 170 ◽  
pp. 03030 ◽  
Author(s):  
Rustem Mukhametrakhimov ◽  
Liliya Lukmanova
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Blended Cement ◽  
Physical And Mechanical Properties ◽  
Hydration Process ◽  
Cement Matrix ◽  
X Ray Diffraction ◽  
Structure Form ◽  
Silicate Phase ◽  
X Ray

The paper studies features of the hydration process of the modified blended cement for fiber cement panels (FCP) using differential thermal analysis, X-ray diffraction analysis, electron microscopy and infrared spectroscopy. It is found that deeper hydration process in silicate phase, denser and finer crystalline structure form in fiber cement matrix based on the modified blended cement. Generalization of this result to the case of fiber cement panels makes it possible to achieve formation of a denser and homogeneous structure with increased physical and mechanical properties.

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.

Recovery, Recrystallization, and Grain-Growth

2019 ◽  
Vol 41 (1) ◽  
pp. 1-1
Author(s):  
Iqra Zubair Awan Iqra Zubair Awan
Keyword(s):  
Mechanical Properties ◽  
State Physics ◽  
Heat Treatment ◽  
Grain Growth ◽  
Structural Damage ◽  
Physical And Mechanical Properties ◽  
Mechanical Deformation ◽  
Solid State Physics ◽  
Science And Engineering ◽  
Thermally Activated

This is a brief review of the important phenomena of recovery, recrystallization as well as grain-growth. The three mentioned phenomena are the mechanisms by which metals and alloys fix the structural damage introduced by the mechanical deformation and, as a consequence, in the physical and mechanical properties. These rehabilitation mechanisms are thermally activated. For this process, the materials have to be heated and any such heat-treatment is meant to reduce deformation-induced break is termed annealing. Other or different heat-treatments lead to recovery and recrystallization. It is rather strange that, though these phenomena are extremely important in metallurgical science and engineering, not so much work has been done as that in corrosion and shape memory technologies. An attempt has been made here to summarize all important aspects of these phenomena for the benefits of students of metallurgy, chemistry and solid state physics.

METAL COMPOSITE MATERIALS BASED ON TITANIUM ALLOYS, REINFORCED WITH REFRACTORY PARTICLES (review)

2021 ◽  
pp. 36-45
Author(s):  
E.I. Krasnov ◽  
◽  
V.M. Serpova ◽  
L.G. Khodykin ◽  
A.V. Gololobov ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Composite Materials ◽  
Literature Review ◽  
Titanium Alloys ◽  
Chemical Nature ◽  
Physical And Mechanical Properties ◽  
Metal Composite ◽  
The Matrix ◽  
Metal Composite Materials

Presents a literature review in the field of methods for strengthening titanium and its alloys by introducing various refractory particles into the matrix. The main problematic issues related to the chemical nature of refractory particles and titanium alloys that arise during hardening are briefly described. The main structural, physical and mechanical properties and morphology of such metal composite materials are described. The dependence of the influence of various refractory particles and their amount, as well as the effect of heat treatment on the physical and mechanical properties of microns based on titanium alloys, is presented.

Contribution of the hybrid component to the structure and properties of ceramics based on metastable phases Al2O3

2021 ◽  
pp. 127-136
Author(s):  
A. V. Maletsky ◽  
T. E. Konstantinova ◽  
D. R. Belichko ◽  
G. K. Volkova ◽  
V. V. Burkhovetsky
Keyword(s):  
Mechanical Properties ◽  
Yttrium Aluminum Garnet ◽  
Metastable Phase ◽  
Physical And Mechanical Properties ◽  
Structure And Properties ◽  
X Ray Diffraction ◽  
Mutual Inhibition ◽  
X Ray ◽  
Tetragonal Lattice ◽  
Yttrium Aluminum

The paper presents results of the study of the effect of doping with yttrium oxide on ceramics of the composition (γ + θ) Al2O3 + nY2O3 (n = 0, 1, 2, 3 wt%), sintered at 1550°C for 2 h, from powders of the specified composition annealed at temperatures of 500 , 800, 1000°С. X-ray diffraction analysis established the formation in ceramics of yttrium aluminum garnet Y3Al5O12 (YAG) and a metastable phase of the same composition with a tetragonal lattice type in powders at temperatures above 1200°C. The effect of YAG on the physical and mechanical properties was established: high properties were demonstrated by ceramics of the composition α-Al2O3 + 2wt% Y2O3, obtained from a powder annealed at 1000°C. In addition, high physical and mechanical properties were observed in ceramics of the composition α-Al2O3 + 0wt% Y2O3, obtained from a powder annealed at 800°C. The effect of the so-called “mutual protection against crystallization” was discovered, which consists in the mutual inhibition of crystallization processes in powders of the Al2O3 – Y2O3 system.

scholarly journals Characterisation of a High-Performance Al–Zn–Mg–Cu Alloy Designed for Wire Arc Additive Manufacturing

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1610 ◽  
Author(s):  
Paulo J. Morais ◽  
Bianca Gomes ◽  
Pedro Santos ◽  
Manuel Gomes ◽  
Rudolf Gradinger ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Additive Manufacturing ◽  
High Performance ◽  
Mechanical Performance ◽  
Fluorescence Analysis ◽  
Cold Metal Transfer ◽  
Direction Parallel ◽  
X Ray ◽  
Wire Arc Additive Manufacturing

Ever-increasing demands of industrial manufacturing regarding mechanical properties require the development of novel alloys designed towards the respective manufacturing process. Here, we consider wire arc additive manufacturing. To this end, Al alloys with additions of Zn, Mg and Cu have been designed considering the requirements of good mechanical properties and limited hot cracking susceptibility. The samples were produced using the cold metal transfer pulse advanced (CMT-PADV) technique, known for its ability to produce lower porosity parts with smaller grain size. After material simulations to determine the optimal heat treatment, the samples were solution heat treated, quenched and aged to enhance their mechanical performance. Chemical analysis, mechanical properties and microstructure evolution were evaluated using optical light microscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray fluorescence analysis and X-ray radiography, as well as tensile, fatigue and hardness tests. The objective of this research was to evaluate in detail the mechanical properties and microstructure of the newly designed high-performance Al–Zn-based alloy before and after ageing heat treatment. The only defects found in the parts built under optimised conditions were small dispersed porosities, without any visible cracks or lack of fusion. Furthermore, the mechanical properties are superior to those of commercial 7xxx alloys and remarkably independent of the testing direction (parallel or perpendicular to the deposit beads). The presented analyses are very promising regarding additive manufacturing of high-strength aluminium alloys.

Effect of heat treatment on mechanical and tribological properties of aluminum metal matrix composites

2020 ◽  
Vol 234 (22) ◽  
pp. 4493-4504
Author(s):  
Manu Sam ◽  
N Radhika ◽  
Katru Pavan Sai
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Wear Rate ◽  
Response Surface ◽  
Surface Deformation ◽  
Wear Test ◽  
Composite Surface ◽  
X Ray ◽  
Mechanical And Tribological Properties ◽  
Sliding Distance

LM25 aluminum alloy reinforced with 10 wt% of TiB2, WC, and ZrO2 were squeeze cast to investigate the effect of T6 heat treatment on tribo-mechanical properties. Among all, WC-reinforced composite achieved superior mechanical properties at the aging time of 8 h. Microstructural examination performed on all composites and alloy concluded that the presence of WC in T6 LM25 caused reduction of α-Al dendrite size, exhibiting superior properties for this composite. X-ray diffraction analysis conducted on alloy and WC-reinforced superior composite revealed formations of phases, which improved their mechanical properties. Energy-dispersive X-ray spectroscopy analysis quantified the actual intensity of WC presence in the superior composite along with its other constituents. Response surface methodology model developed for wear test of the superior composite involves parametric range like applied load (10–50 N), sliding velocity (1–4 m/s), and sliding distance (500–2500 m). Analysis of variance along with regression analysis proved that, statistical analytical model developed good relationship between the actual wear rate and process parameters. Response surface plots represented the linearly increasing wear trend with respect to load and sliding distance. Wear rate dropped initially and raised later on along with velocity. Scanning electron microscopy exhibited the surface deformation prevailing on the composite surface at high load.

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