scholarly journals SIMULATED HEAT AFFECTED ZONE IN WELDED STAINLESS STEEL 304L

2019 ◽  
Vol 25 (3) ◽  
pp. 142 ◽  
Author(s):  
Soumia HAMZA ◽  
Zakaria BOUMERZOUG ◽  
Elhadj RAOUACHE ◽  
Fabienne DELAUNOIS
Keyword(s):  
Stainless Steel ◽  
Heat Affected Zone ◽  
Thermal Cycle ◽  
Welded Joint ◽  
Rapid Heating ◽  
X Ray ◽  
Stainless Steel 304L ◽  
Heating And Cooling ◽  
Cycle Simulation ◽  
Scanning Electron

<p>This work is a contribution study of the heat-affected zone in the real welded joint of stainless steel 304L. This zone was compared to the heat-affected zone obtained by using a thermal cycle simulation of welding. This experimental technique is based on thermal cycle simulation of welding by rapid heating and cooling treatments of the base metal in a specific simulation equipment. The samples were analyzed by scanning electron microscopy equipped with energy dispersive X-ray, and microhardness measurements. Microstructures and mechanical properties of the simulated heat affected zone were also determined. Thermal cycle simulation technique has revealed more details on the microstructure and the mechanical behavior of the heat-affected zone.</p>

Thermal Cycle Simulation of Welding Process in INC 738 LC Superalloy

2017 ◽  
Vol 735 ◽  
pp. 75-79
Author(s):  
Zakaria Boumerzoug ◽  
Saib Cherif
Keyword(s):  
Optical Microscopy ◽  
Thermal Cycle ◽  
Welded Joint ◽  
Rapid Heating ◽  
Welding Process ◽  
The Real ◽  
Temperature Range ◽  
Characterization Techniques ◽  
Heating And Cooling ◽  
Cycle Simulation

This paper is a contribution to the study of the microstructure in welded joint of INC 738 LC. It presents the microstructures obtained after real welding and also after thermal cycle simulation of welding by rapid heating and cooling treatments in specific simulation equipment. We were focusing on the temperature range [900°C, 1100°C] which is the temperature range of main phases occurrence, as coarse γ’primary, fine γ’ secondary and carbides. Optical microscopy and microhardness measurements were used as characterization techniques. We have found that the obtained microstructures by thermal cycle simulation of welding correspond to those observed in the same zone of the real welded joint performed by real welding.

scholarly journals QPOs in compact binaries from small scale eruptions in an inner magnetized disk

2020 ◽  
Author(s):  
Nicolas Scepi ◽  
Mitchell C Begelman ◽  
Jason Dexter
Keyword(s):  
Rapid Heating ◽  
Small Scale ◽  
Type B ◽  
Periodic Oscillations ◽  
X Ray ◽  
Compact Binaries ◽  
Heating And Cooling ◽  
Low Mass ◽  
X Ray Binaries ◽  
Standard Disk

Abstract Dwarf novæ (DNe) and low mass X-ray binaries (LMXBs) are compact binaries showing variability on time scales from years to less than seconds. Here, we focus on explaining part of the rapid fluctuations in DNe, following the framework of recent studies on the monthly eruptions of DNe that use a hybrid disk composed of an outer standard disk and an inner magnetized disk. We show that the ionization instability, that is responsible for the monthly eruptions of DNe, is also able to operate in the inner magnetized disk. Given the low density and the fast accretion time scale of the inner magnetized disk, the ionization instability generates small, rapid heating and cooling fronts propagating back and forth in the inner disk. This leads to quasi-periodic oscillations (QPOs) with a period of the order of 1000 s. A strong prediction of our model is that these QPOs can only develop in quiescence or at the beginning/end of an outburst. We propose that these rapid fluctuations might explain a subclass of already observed QPOs in DNe as well as a, still to observe, subclass of QPOs in LMXBs. We also extrapolate to the possibility that the radiation pressure instability might be related to Type B QPOs in LMXBs.

Tests and Discussions on the Impact Work of the S30403 Austenitic Stainless Steel at 20°C and -196°C

2013 ◽  
Author(s):  
Zhiwei Chen ◽  
Guoyi Yang ◽  
Caifu Qian ◽  
Xiang Li ◽  
Haoyang Wang
Keyword(s):  
Stainless Steel ◽  
Austenitic Stainless Steel ◽  
Cross Section ◽  
Heat Affected Zone ◽  
Welded Joint ◽  
Base Plate ◽  
Testing Environment ◽  
Impact Tests ◽  
The Impact

In this paper, impact tests on the S30403 austenitic stainless steel at 20°C as well as −196°C were carried out. Both base plate and welded joint including weld and heat-affected zone are tested to measure the impact work KV2. It is found that when the temperature of the testing environment is decreased from 20°C to −196°C, both the impact work KV2 for the base plate and welded joint are decreased remarkably. Specifically, the impact work KV2 for the base plate decreases by 19–29% while that for the welded joint decreases by as much as 53.8%. In addition, impact tests with different size of specimens show the impact work KV2 with 5×10×55mm specimens is about 0.53–0.54 times that with 7.5×10×55mm specimens, much lower than 2/3, the ratio of two specimens’ cross section areas, indicating that rules in relevant steel or equipment standards regarding impact tests using small specimens need to be revised.

Effect of Thermal Cycle on Microstructure and Corrosion Behavior of Duplex Stainless Steel SAF 2205 Electron Beam Welded Joint

2018 ◽  
Vol 786 ◽  
pp. 119-127
Author(s):  
Sameh M. Khafagy ◽  
Morsy Amin Morsy ◽  
H.M. El Sherbini ◽  
Y.F. Barakat
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Duplex Stainless Steel ◽  
Thermal Cycle ◽  
Welded Joint ◽  
Volume Fraction ◽  
Holding Time ◽  
Σ Phase ◽  
Phase Volume Fraction ◽  
Saf 2205

It is known that heat treatment (HT) highly affects the properties of base metal (BM) and fusion zones (FZ) of duplex stainless steel (DSS). In fact, it may give unwanted structure changes. Duplex stainless steels SAF 2205 welded joint was subjected to thermal cycle at temperature of 850◦C at holding times 1, 3, 5 and 7 hours. The influence of heating cycles and concentration of corrosive medium on the corrosion properties and microstructure of 2205 alloy was the objective of this work. It was found that process led to noticeable decrease in the corrosion resistance of BM and FZ specimens; moreover the decrease was large in BM than FZ. It was also found that sigma phase (σ) precipitated in the different zones of the structure. σ phase volume fraction was found to increase with increasing the holding time of HT, and its increase is larger in BM. Corrosion resistance was found to be oppositely related to σ phase formation. Secondary austenite phase (γ2) was also precipitated and its volume fraction in FZ was found to increase with increasing the holding time of HT and decreased in BM.

Stainless Steel 316 L Metal Coating with Capiz Shell Hydroxyapatite Using Electrophoretic Deposition Method as Bone Implant Candidate

2020 ◽  
Vol 840 ◽  
pp. 336-344
Author(s):  
Martinus Kriswanto ◽  
Muhammad Khairurrijal ◽  
Dave Leonard Junior Wajong ◽  
Tofan Maliki Kadarismanto ◽  
Yusril Yusuf
Keyword(s):  
Stainless Steel ◽  
Electrophoretic Deposition ◽  
Sintering Temperature ◽  
Deposition Method ◽  
Stainless Steel 316L ◽  
Bone Implant ◽  
X Ray ◽  
Withdrawal Speed ◽  
Stainless Steel 316 ◽  
Scanning Electron

Hydroxyapatite (HAp) made of capiz shell has been successfully coated onto stainless steel 316L substrate using electrophoretic deposition (EPD) method. In this study, three variations were applied, they were the voltages of 25 V and 50 V, the withdrawal speeds of 0.1 mm/s, 0.5 mm/s, and 1 mm/s, and the sintering temperatures of 750, 850, and 950 °C. These variations were applied to determine the differences in morphology and crystal structure of the layers so that the most suitable result was obtained as a candidate for the bone implant. Characterization was done by Scanning Electron Microscope and X-Ray Diffractometer. The EPD process and the application of sintering temperature eliminated the phase of B type apatite carbonate which made the purity of the HAp layer higher. The SEM results show that the layer was more homogeneous and free of cracking at a voltage of 50 V and the withdrawal speed of 0.1 mm/s. The layer density was higher as the voltage and sintering temperature increased. Higher sintering temperature also made the layer more homogeneous, but at 950 °C, stainless steel 316L substrate underwent a phase transformation which caused the decreasing of the purity of the HAp layer. The best results were obtained by applying a50 V voltage, a withdrawal speed of 0.1 mm/s, and a sintering temperature of 850 °C.

Electrodeposition of Aluminum on 316L Stainless Steel from Molten Salts Based on Chlorides

2008 ◽  
Vol 373-374 ◽  
pp. 273-276 ◽  
Author(s):  
Yu Jiang Wang ◽  
Xin Xin Ma ◽  
Guang Wei Guo
Keyword(s):  
Stainless Steel ◽  
Cross Section ◽  
Molten Salts ◽  
Single Phase ◽  
316L Stainless Steel ◽  
Aluminum Layer ◽  
X Ray Diffraction ◽  
X Ray ◽  
High Purity Aluminum ◽  
Scanning Electron

The electrodeposition of aluminum on 316L stainless steel from a molten salts based on chloride has been studied. The surface morphology of the aluminum layer has been examined through scanning electron microscope (SEM) and the structure of the aluminum layer has been analyzed by X-ray diffraction (XRD). The thickness of the deposited aluminum layer has been measured by the method of cross-section scan. It has been suggested that a white, smooth, non-porous and a high purity aluminum layer can be obtained on 316L stainless steel from the ternary chloride molten salts (AlCl3 – NaCl - KCl). And the structure of the aluminum layer was single-phase.

Modification of Microstrucure and Residual Stress on Friction Welding Surface of Titanium Alloy by Water-Jet Cavitation Peening

2011 ◽  
Vol 317-319 ◽  
pp. 429-435 ◽  
Author(s):  
Dong Ying Ju ◽  
Xin Mao Fu ◽  
Shun Na ◽  
Bing Han ◽  
Xiao Hu Deng
Keyword(s):  
Electron Microscopy ◽  
Residual Stress ◽  
Welded Joints ◽  
Compressive Residual Stress ◽  
Welded Joint ◽  
Water Jet ◽  
X Ray Diffraction ◽  
X Ray ◽  
Welding Surface ◽  
Scanning Electron

Water jet cavitation peening is applied to improve the strength and mechanical properties of the friction-welded joints of titanium alloys. Scanning electron microscopy observations of the microstructure of the welded joints and welded area before/after water jet cavitation peening confirm slip dislocation at the microstructure near the surface of the specimens. The residual stress on the surface of the welded joint is measured by X-ray diffraction. The results indicate the effect of peening time on the strength of compressive residual stress.

Effection of Additive on Aluminum Nitride Nano-Wire Synthesis by Double Decomposition Method

2013 ◽  
Vol 744 ◽  
pp. 428-431
Author(s):  
Yan Long Sun ◽  
Li Min Dong ◽  
Tao Jiang ◽  
Cao Guo ◽  
Xiao Qi Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Stainless Steel ◽  
Aluminum Nitride ◽  
Decomposition Method ◽  
Average Diameter ◽  
X Ray Diffraction ◽  
X Ray ◽  
Double Decomposition ◽  
Scanning Electron

An method for making AlN(aluminum nitride) nanowires by double decomposition, and the effection of additives was described. Future more, the growth mechanism of AlN nanowire synthesis with addictive were analyzed. AlN nanowire were synthesis by he AlCl3 and NaN3 in stainless steel cauldron without solvent and using Mg and Zn as additive. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to study characters of the AlN nanowire. It is shown that the process can produce AlN nanowire with mean diameters ranging from 50 to 100 nm at 450°C. The additive has effective facilitated on the synthesis of aluminum nitride nanowires, can improve the properties of aluminum nitride nanowire, minish the average diameter of aluminum nitride nanowires.

Correlation between microstructural gradient and microindentation properties of dissimilar weld between INCONEL 625 and Duplex Stainless Steel

2020 ◽  
Vol 117 (4) ◽  
pp. 407
Author(s):  
Ammar Chabbi ◽  
Mabrouk Bouabdallah ◽  
Sergio Sao-Joao ◽  
Achraf Boudiaf ◽  
Guillaume Kermouche
Keyword(s):  
Stainless Steel ◽  
Elastic Modulus ◽  
Weld Metal ◽  
Duplex Stainless Steel ◽  
Heat Affected Zone ◽  
Laves Phase ◽  
Inconel 625 ◽  
Secondary Phases ◽  
Dissimilar Weld ◽  
Scanning Electron

Microstructure evolution and microindentation properties of dissimilar weld between Inconel 625 nickel based alloy and UNS S32205 Duplex Stainless Steel have been investigated in the current study. Samples in cross-section areas were prepared to investigate microstructure and micromechanical properties in different regions of weld using optical microscopy, scanning electron microscopy and indentation measurements. Typical solidification microstructures were observed. Secondary phases were noticed in both the weld metal and heat affected zone of Inconel 625 alloy at cellular and interdendritic region in lamellar, rod shaped and cuboidal form. These secondary phases were identified as Laves phase and carbonitrides of Nb and Ti. Mechanical properties including elastic modulus and hardness were estimated across the weld joint. The results showed that the weld metal exhibit the lowest values of hardness and elastic modulus, however the Heat Affected Zone of the stainless steel exhibit the highest values owing to high δ-ferrite amount. In-situ nanoindentation coupled with Scanning Electron Microscope was carried out in Laves phase and the matrix weld in order to evaluate nanohardness. The result showed that the nanohardness of Laves phase is too great compared to the weld matrix.

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