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Investigation of Impact Behavior of TIG Welded Inconel 718 at Aircraft Engine Operating Temperatures
Online since: March 2017
Authors: Yagiz Uzunonat
Rapid grain growth and γ′′→δ transformation as a result causes a decrease in the material properties in the applications above 650oC.
Results and Discussion For the facilitation in comparison of experimental data, specimens were numbered and separated into two groups as Welded (W) and Non-Welded (NW).
Six hardness values obtained from the different samples and their specimen numbers are given in Table 2.
Results and Discussion For the facilitation in comparison of experimental data, specimens were numbered and separated into two groups as Welded (W) and Non-Welded (NW).
Six hardness values obtained from the different samples and their specimen numbers are given in Table 2.
Online since: April 2005
Authors: Ayako Oyane, Atsuo Ito, Yousuke Ishihara, Masaki Uchida
The EVOH substrate was abraded with a sandpaper (SiC with an average grain size of 10 µm),
ultrasonically washed with acetone and ethanol, and then dried at 100°C under vacuum for 24 h.
After CaP treatment (Fig. 2, b), TEM image showed a number of particles newly deposited on the specimen surface.
The ACP particulate observed in Fig. 2 (b) disappeared, leaving a layer consisting of a large number of needle-like substances.
After CaP treatment (Fig. 2, b), TEM image showed a number of particles newly deposited on the specimen surface.
The ACP particulate observed in Fig. 2 (b) disappeared, leaving a layer consisting of a large number of needle-like substances.
Online since: April 2005
Authors: Christian Kaddick, Thomas Oberbach, Wilfried Glien
The medium grain size led
between 180 - 250 microns [fig. 1]
Figure 1
SEM photograph of the prepared alumina particles To realize the presence of alumina particles in the artificial joint gap during the simulator study 1g
of the alumina powder was pressed into the gap before testing and after each inspection after 0.5
mio cycles.
Engh, MD: Analysis of prosthetic femoral heads retrieved at autopsy; Clinical orthopaedics and related research, Number 358, pp 223 - 234 [2] Matziolis, G., Perka, C.: Metallose nach Ersatz eines frakturierten Keramikkopfes durch einen Metallkopf; Fallbericht und Literaturübersicht; 52.
Jobbins: Ceramic bearing surfaces in total artificial joints: resistance to third body wear damage from bone cement particles; Journal of Medial Engineering & Technology, Volume 15, Number 2, (March/April 1991), 63 - 67 [4] A.
Engh, MD: Analysis of prosthetic femoral heads retrieved at autopsy; Clinical orthopaedics and related research, Number 358, pp 223 - 234 [2] Matziolis, G., Perka, C.: Metallose nach Ersatz eines frakturierten Keramikkopfes durch einen Metallkopf; Fallbericht und Literaturübersicht; 52.
Jobbins: Ceramic bearing surfaces in total artificial joints: resistance to third body wear damage from bone cement particles; Journal of Medial Engineering & Technology, Volume 15, Number 2, (March/April 1991), 63 - 67 [4] A.
Online since: March 2015
Authors: Rui Niu, Wei Sun, Lei Huo, Fu Tao Qu, Teng Yun Xie, Lei Cao
Petrology Characteristics of Reservoir
According to the analyzed of 702 cast thins, the lithology of Chang 6 reservoir is fine-grained lithic feldspar sandstone, followed by feldspar lithic sandstone in research area (Fig.1).
Throat is generally small, poor connectivity between pores, because of the clogging; throat coordination number is low and the seeping ability becoming worse [3].
Table.1 Laboratory results of samples in the Banqiao—Heshui area with nuclear magnetic resonance technique Serial number porosity [%] Permeability [10-3μm2] Movable fluid saturation [%] Movable fluid porosity [%] Irreducible water saturation [%] classification 1 9.70 0.120 27.77 2.69 72.23 IV 2 10.19 0.100 42.72 4.49 57.28 III 3 9.68 0.070 40.47 3.93 59.53 III 4 8.34 0.100 37.03 3.18 62.97 III 5 16.12 1.220 29.89 4.54 70.11 IV 6 10.51 0.490 33.95 3.46 66.05 IV Average 10.76 0.35 35.31 3.72 64.69 The distribution of No.1 sample’s T2 spectrum frequency is asymmetric unimodal, the limit value of relaxation time on the left side of the area significantly greater than the right side of the area.
Throat is generally small, poor connectivity between pores, because of the clogging; throat coordination number is low and the seeping ability becoming worse [3].
Table.1 Laboratory results of samples in the Banqiao—Heshui area with nuclear magnetic resonance technique Serial number porosity [%] Permeability [10-3μm2] Movable fluid saturation [%] Movable fluid porosity [%] Irreducible water saturation [%] classification 1 9.70 0.120 27.77 2.69 72.23 IV 2 10.19 0.100 42.72 4.49 57.28 III 3 9.68 0.070 40.47 3.93 59.53 III 4 8.34 0.100 37.03 3.18 62.97 III 5 16.12 1.220 29.89 4.54 70.11 IV 6 10.51 0.490 33.95 3.46 66.05 IV Average 10.76 0.35 35.31 3.72 64.69 The distribution of No.1 sample’s T2 spectrum frequency is asymmetric unimodal, the limit value of relaxation time on the left side of the area significantly greater than the right side of the area.
Online since: September 2018
Authors: Getúlio de Vasconcelos, Ana Claudia Costa Oliveira, Maria Fernanda Souza Ferreira, Silvelene Alessandra Silva, Glaucia Regina Pita
Introduction
Thermal barrier coatings continue to be the subject of a number of worldwide surveys that seek and offer new solutions for each new proposed situation and seek improvements in performance, reliability and durability of conventional coatings.
This process prevents the oxidation of the substrate from occurring and still maintains certain porosity inside the coating, obtaining a surface more resistant to the impacts with sand grains common in aircraft turbines in landings and takeoffs [7].
The number of ball turns and the normal force on the sample are supplied by the apparatus.
This process prevents the oxidation of the substrate from occurring and still maintains certain porosity inside the coating, obtaining a surface more resistant to the impacts with sand grains common in aircraft turbines in landings and takeoffs [7].
The number of ball turns and the normal force on the sample are supplied by the apparatus.
Online since: December 2013
Authors: Ya Li Wang, Su Ping Cui, Yan Yao, Ming Ming Hou
Table1 Sample number and description
name
description
limestone(A10)
without pre-calcination
limestone(A20)
pre-calcination with 900ºC
limestone(A30)
pre-calcination with 1000ºC
limestone(A40)
pre-calcination with 1100ºC
limestone(A50)
pre-calcination with 1200ºC
cement raw material(A1)
without pre-calcination
cement raw material(A2)
pre-calcination with 900ºC
cement raw material(A3)
pre-calcination with 1000ºC
cement raw material(A4)
pre-calcination with 1100ºC
cement raw material(A5)
pre-calcination with 1200ºC
Table2 The chemical composition of limestone
name
Loss
SiO2
Al2O3
Fe2O3
CaO
MgO
K2O
SO3
A10
40.83
3.62
0.96
1.12
50.58
2.08
0.20
0.27
A20
34.34
4.02
1.06
1.25
56.12
2.31
0.22
0.30
A30
30.35
4.33
1.15
1.26
59.31
2.47
0.25
0.39
A40
27.65
4.41
1.17
1.24
61.75
2.61
0.26
0.41
A50
23.21
4.71
1.23
1.30
65.74
2.76
0.28
0.42
Sandstone
-
74.22
12.84
5.07
0.62
0.76
-
0.20
Experimental Process
Presinter: Limestone and raw materials around 5 gram were placed directly at 850ºC
Table 3 The raw material of different calcining temperature of limestone addition proportion (%) Sample A11 A22 A33 A44 A55 Limestone 77.33 75.45 74.48 73.63 72.41 Sandstone 22.67 24.55 25.52 26.37 27.59 Table 4 The chemical composition of raw material (%) Name Loss SiO2 Al2O3 Fe2O3 CaO MgO K2O SO3 A11 32.16 19.63 3.65 2.02 39.25 1.78 0.15 0.26 A22 26.55 21.25 3.95 2.18 42.50 1.93 0.17 0.28 A33 23.27 22.16 4.14 2.23 44.33 2.04 0.19 0.34 A44 21.05 22.82 4.25 2.25 45.63 2.12 0.19 0.35 A55 17.52 23.89 4.43 2.34 47.78 2.21 0.20 0.36 Table5 The results of different calcining clinker in test temperature Number of samples A11 A22 A33 A44 A55 CaO content after calcination (wt %) 5.18 4.47 4.87 5.19 6.71 CaO content before calcination (wt %) 57.86 57.86 57.77 57.80 57.93 Reaction content (wt %) 52.68 53.39 52.90 52.61 51.21 Fig. 1 The reaction percentage of calcium oxide in clinker at different presenter temperature As can be seen from Table5 and Fig.1, after limestone
Temperature increasing speeds up the crystal growth, and coarse grains reduces the reaction rate, thus, during the test temperature, the activity decreases gradually.
Table 3 The raw material of different calcining temperature of limestone addition proportion (%) Sample A11 A22 A33 A44 A55 Limestone 77.33 75.45 74.48 73.63 72.41 Sandstone 22.67 24.55 25.52 26.37 27.59 Table 4 The chemical composition of raw material (%) Name Loss SiO2 Al2O3 Fe2O3 CaO MgO K2O SO3 A11 32.16 19.63 3.65 2.02 39.25 1.78 0.15 0.26 A22 26.55 21.25 3.95 2.18 42.50 1.93 0.17 0.28 A33 23.27 22.16 4.14 2.23 44.33 2.04 0.19 0.34 A44 21.05 22.82 4.25 2.25 45.63 2.12 0.19 0.35 A55 17.52 23.89 4.43 2.34 47.78 2.21 0.20 0.36 Table5 The results of different calcining clinker in test temperature Number of samples A11 A22 A33 A44 A55 CaO content after calcination (wt %) 5.18 4.47 4.87 5.19 6.71 CaO content before calcination (wt %) 57.86 57.86 57.77 57.80 57.93 Reaction content (wt %) 52.68 53.39 52.90 52.61 51.21 Fig. 1 The reaction percentage of calcium oxide in clinker at different presenter temperature As can be seen from Table5 and Fig.1, after limestone
Temperature increasing speeds up the crystal growth, and coarse grains reduces the reaction rate, thus, during the test temperature, the activity decreases gradually.
Online since: March 2014
Authors: Wojciech Napadłek, Adam Woźniak
The samples were flooded in with an epoxy resin and then were polished using abrasive papers with grit from 100 to 2000 and polished on the polishing disks with diamond powder with a grain size of 3 µm and 0,5 µm and aluminum oxides.
The topography of the side surface of the rod after laser texturing: laser Nd:YAG λ=1064 nm, power - 50W, frequency 3kHz, scan speed 500 mm/s, distance between the lines 0,15 mm, number of pulses in the same area - 20 In the second variant of the side surface laser texturing of the rod was prepared layout of oil tanks in the shape of microchannels with microextrusions (Fig. 3).
Surface topography and the geometry of the microchannels oil, made with the laser ablation of the side surface area: laser Nd:YAG, λ=1064 nm, power - 50W, frequency 3 kHz, speed 25 mm/s, number of pulses in the same area - 15 A technological variant of ablative laser texturing with of 50% filling level of the microcontainers of the modified by laser surface of steel was also manufactured.
The topography of the side surface of the rod after laser texturing: laser Nd:YAG λ=1064 nm, power - 50W, frequency 3kHz, scan speed 500 mm/s, distance between the lines 0,15 mm, number of pulses in the same area - 20 In the second variant of the side surface laser texturing of the rod was prepared layout of oil tanks in the shape of microchannels with microextrusions (Fig. 3).
Surface topography and the geometry of the microchannels oil, made with the laser ablation of the side surface area: laser Nd:YAG, λ=1064 nm, power - 50W, frequency 3 kHz, speed 25 mm/s, number of pulses in the same area - 15 A technological variant of ablative laser texturing with of 50% filling level of the microcontainers of the modified by laser surface of steel was also manufactured.
Online since: June 2014
Authors: Pongpan Chindaudom, Supanit Porntheeraphat, Jiti Nukeaw, Siraphat Pratontep, Pitak Eiamchai, Mati Horprathum, Chanunthorn Chananonnawathorn, Darinee Phromyothin, Narathon Khemasiri
To fabricate these protective coatings, a number of good candidates include titanium dioxide (TiO2), chromium nitride (CrN), niobium oxide (NbO), and tantalum oxide (Ta2O5).
This was probably because of the diffusion of the reagent along the grain boundaries.[1] Fig. 2 I-V polarization curve (Tafel slope) of the samples after immersed in 1M NaCl (a) bare (uncoated) substrate and 25 nm-Ta2O5 sample; and (b) Ta2O5 films at various thicknesses In order to determine the corrosion rate, we recalled the current density which was directly related with the corrosion rate, from the following equation: (1) Where RM is the corrosion rate (mm/year), M is the atomic weight, n is the charge number, F is the Faraday’s constant (94.485 C/mol), and r is the density.
This was probably because of the diffusion of the reagent along the grain boundaries.[1] Fig. 2 I-V polarization curve (Tafel slope) of the samples after immersed in 1M NaCl (a) bare (uncoated) substrate and 25 nm-Ta2O5 sample; and (b) Ta2O5 films at various thicknesses In order to determine the corrosion rate, we recalled the current density which was directly related with the corrosion rate, from the following equation: (1) Where RM is the corrosion rate (mm/year), M is the atomic weight, n is the charge number, F is the Faraday’s constant (94.485 C/mol), and r is the density.
Online since: August 2013
Authors: Shun Wen Ji, Lei Jiang, Qi Huan Shi
Table 1 Material parameters of Baixi CFRD
Number
φ
K
n
Rf
Kb
m
1
51
1.14
0.26
0.79
611
0.09
2
49
1.21
0.28
0.76
621
0.14
3
45
1.07
0.33
0.76
425
0.03
In this study, the contact conditions between face slab and dam body, as well as face slab itself and with toe slab are simulated, by using interface element.
For the face slab with stake number 0+70.0 to 0+110.0, the tensile stress along the slope almost exceedes 2.0MPa.
M. and Xu Q., Research on increment creep model of coarse grained materials, Rock and Soil Mechanics, 32 (11)(2011) 3201-3496.
For the face slab with stake number 0+70.0 to 0+110.0, the tensile stress along the slope almost exceedes 2.0MPa.
M. and Xu Q., Research on increment creep model of coarse grained materials, Rock and Soil Mechanics, 32 (11)(2011) 3201-3496.
Online since: November 2013
Authors: Roman Gröger
This represents a major problem in multiscale modeling of materials whose goal is to develop a systematic coarse-graining procedure through which the essential atomic-level details of the problem can be projected into macroscopic laws or continuum models.
Theoretical background In the following, we will discretize the simulated body into a finite number of mesoscopic cells (mesocells) that can contain from a few to thousands of unit cells.
Moreover, any mesocell may be either dislocation-free or contain a finite number of crystal dislocations.
Theoretical background In the following, we will discretize the simulated body into a finite number of mesoscopic cells (mesocells) that can contain from a few to thousands of unit cells.
Moreover, any mesocell may be either dislocation-free or contain a finite number of crystal dislocations.