scholarly journals Development of Low-Magnetic-Permeability Welds of 316L Stainless Steel

2021 ◽  
Vol 100 (10) ◽  
pp. 323-337
Author(s):  
ABHAY KUMAR ◽  
◽  
PUPPALA GANESH ◽  
VISHNU KUMAR SHARMA ◽  
MEGHMALHAR MANEKAR ◽  
...  
Keyword(s):  
Stainless Steel ◽  
Magnetic Permeability ◽  
316L Stainless Steel ◽  
Construction Material ◽  
Pressure Vessels ◽  
Particle Accelerator ◽  
Particle Accelerators ◽  
Shielding Gas ◽  
Vacuum Chambers ◽  
The Impact

Austenitic stainless steel is often used as the construction material for particle accelerator vacuum chambers. It is also a strong candidate construction material for helium vessels of superconducting radiofrequency cavities of highenergy, high-power particle accelerators. One of the major limitations of austenitic stainless steels for their application in particle accelerators is the relatively higher magnetic permeability of its welds. The present paper describes an experimental study to obtain a low-magnetic-permeability gas tungsten arc weld of 316L stainless steel while using ER 316L stainless steel filler metal through controlled addition of nitrogen in the argon shielding gas. It was demonstrated that 316L stainless steel welds, made with the addition of 1.5% nitrogen in the argon shielding gas, were associated with magnetic permeability close to that of the base metal. The welds exhibited good strength and ductility in addition to qualifying the impact test requirement of the American Society of Mechanical Engineers Boiler & Pressure Vessel Code (BPVC) for operation at room temperature and liquid helium temperature (4 K). The technique is important for the fabrication of BPVC-compliant 316L stainless steel vacuum chambers and pressure vessels of particle accelerators, including helium vessels of superconducting radiofrequency cavities.

Effects of nitrogen and hydrogen in argon shielding gas on bead profile, delta-ferrite and nitrogen contents of the pulsed GTAW welds of AISI 316L stainless steel

2016 ◽  
Vol 58 (6) ◽  
pp. 489-494 ◽  
Author(s):  
Panyasak Phakpeetinan ◽  
Amnuysak Chianpairot ◽  
Ekkarut Viyanit ◽  
Fritz Hartung ◽  
Gobboon Lothongkum
Keyword(s):  
Stainless Steel ◽  
316L Stainless Steel ◽  
Aisi 316L ◽  
Shielding Gas ◽  
Delta Ferrite ◽  
Aisi 316L Stainless Steel ◽  
Pulsed Gtaw ◽  
Nitrogen Contents ◽  
Bead Profile

Microstructure and Corrosion Resistance of HVOF Sprayed 316L Stainless Steel and Ni Base Alloy Coatings

2000 ◽  
Author(s):  
S. Kuroda ◽  
T. Fukushima ◽  
T. Kodama ◽  
M. Sasaki
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
316L Stainless Steel ◽  
Sea Water ◽  
Base Alloy ◽  
Standard Condition ◽  
Polarization Measurement ◽  
Superior Corrosion Resistance ◽  
Distribution Composition ◽  
The Impact

Abstract 316L stainless steel and Hastelloy C alloy powders were sprayed by an HVOF apparatus onto mild steel substrates. The microstructure, pore size distribution, composition and corrosion resistance of thus obtained coatings were evaluated experimentally. Corrosion resistance in sea-water was examined by monitoring the impedance and corrosion potential of samples immersed in artificial sea-water at 300 K over a period of more than 3 months and also by polarization measurement. It was found that the stainless coatings composed mainly of plastically deformed particles and some splats which were molten at the impact. By increasing the combustion pressure, the porosity as measured by mercury porosimeter could be reduced to below 1%. In comparison, Hastelloy C deposits sprayed under the standard condition were so dense that its porosity could not be measured by the porosimeter. The polarization curve and the results of impedance monitoring both exemplified that the Hastelloy C coatings possess much superior corrosion resistance to the stainless coatings in sea-water, which was attributed to the higher density and better adhesion of the Ni-base alloy coatings.

Effect of Ar-N2 Mixed Gas on Morphology and Microstructure of Type 316L Stainless Steel TIG Weld Metal

2011 ◽  
Vol 295-297 ◽  
pp. 1919-1924 ◽  
Author(s):  
Kuang Hung Tseng ◽  
Kai Chieh Hsien
Keyword(s):  
Stainless Steel ◽  
Weld Metal ◽  
316L Stainless Steel ◽  
Welding Process ◽  
Ferrite Content ◽  
Shielding Gas ◽  
Mixed Gas ◽  
Nitrogen Gas ◽  
Type 316L ◽  
Type 316L Stainless Steel

The aim of the present work was to investigate the effects of specific nitrogen gas additions to argon shielding gas on morphology and microstructure of austenitic stainless steel TIG welds. An autogenous TIG welding process was applied on type 316L stainless steel to produce a bead-on-plate weld. The ferrite content of weld metal was measured using a Feritscope. The results indicated that the arc voltage increase as the amount of nitrogen gas added to the argon atmosphere increases. The retained ferrite content of type 316L stainless steel TIG weld metal decreased rapidly as nitrogen gas addition to the argon shielding gas was increased.

Recrystallization and Grain Growth Behavior of SPD Deformed 316L Stainless Steel

2010 ◽  
Vol 89-91 ◽  
pp. 491-496
Author(s):  
Stephan Scheriau ◽  
Thomas Schöberl ◽  
Siegfried Kleber ◽  
Reinhard Pippan
Keyword(s):  
Stainless Steel ◽  
316L Stainless Steel ◽  
High Pressure Torsion ◽  
Equivalent Strain ◽  
Subsequent Annealing ◽  
Large Strains ◽  
Fine Grained ◽  
Saturation Region ◽  
Coarse Grains ◽  
The Impact

The microstructural evolution, the changes in microhardness and the recrystallization behavior of a modified 316L stainless steel were investigated during high pressure torsion (HPT) and subsequent annealing. To study the impact of the governing process parameters on the evolving microstructures, the applied strain, the strain path and the annealing temperatures were varied. In contrast to ordinary single phase steels, which showed a decrease in the structural size ending in a saturation of the microstructural refinement between an equivalent strain eq of 10 and 15, HPT of the modified 316L results in a steep increase in shear stress at very small strains and the saturation region is reached far before eq = 10. Studies using the transmission electron microscope (TEM) revealed that at large strains the original coarse grains are converted by the massive intersection and fragmentation of twins into a nanometer-scaled microstructure. In the case of monotonic HPT, shock annealing of the deformed discs results in rows of fine and coarse grains. In the cyclic deformed discs a homogenous, fine-grained and almost fully recrystallized microstructure was observed. The results clearly show that both the strength and ductility of the material can be significantly influenced by SPD and subsequent annealing. Possible reasons for the observed differences in the deformation and annealing behavior are discussed.

scholarly journals Industrial Safety at Particle Accelerators

2020 ◽  
pp. 83-116
Author(s):  
Thomas Otto
Keyword(s):  
Best Practice ◽  
Pressure Vessels ◽  
Particle Accelerator ◽  
Industrial Safety ◽  
Environmental Damage ◽  
Mechanical Equipment ◽  
Particle Accelerators ◽  
Occupational Hazards ◽  
Occupational Noise ◽  
Safety Hazards

AbstractThe construction and operation of particle accelerators implies the use of numerous technologies and trades which are well-known from the manufacturing and construction industries. Consequently, their safety hazards are described in the literature and standard best practice solutions exist for controlling the risks emerging from these activities. In this section, the occupational hazards of electricity, mechanical equipment and pressure vessels are illustrated with examples from particle accelerator facilities. Further sections are dedicated to accelerator-specific protection against fire, occupational noise, and environmental damage.

Microstructure and Corrosion Characteristics of Selective Laser-Melted 316L Stainless Steel: The Impact of Process-Induced Porosities

JOM ◽  
2019 ◽  
Vol 71 (9) ◽  
pp. 3230-3240 ◽  
Author(s):  
M. Kazemipour ◽  
M. Mohammadi ◽  
E. Mfoumou ◽  
A. M. Nasiri
Keyword(s):  
Stainless Steel ◽  
316L Stainless Steel ◽  
The Impact

scholarly journals Evaluation of Strain Distribution for the P91 Steel under Static Load Using Espi System

2014 ◽  
Vol 14 (4) ◽  
pp. 28-39
Author(s):  
P. Grzywna ◽  
D. Kukla
Keyword(s):  
Static Load ◽  
Construction Material ◽  
Pressure Vessels ◽  
Resistant Steel ◽  
P91 Steel ◽  
Steel Pipes ◽  
Material State ◽  
Service Conditions ◽  
Distribution Of Stress ◽  
The Impact

AbstractThe goal of the research was to evaluate the change of displacement/strain phases in the P91 steel under static load conditions. Undertaken tests were aimed at estimation and analysis of the impact of the material state, which was subjected to loading conditions, on the distribution of stress pattern using ESPI system. Specimen made of high temperature creep resistant steel X10CrMoVNb9-1 (P91) used as a construction material for boiler steam feed heaters, vapor tanks, pressure vessels and vapor pipelines, is used in the service conditions of temperature range up of 650°C. Test samples were taken from two P91 steel pipes. One sample came from a segment of a pipeline transporting fresh vapor in time 80 000 h, under the pressure of 8.4 MPa and temperature 540 °C. The second sample was the same material but in the delivery state.

scholarly journals Charpy Impact Properties of Hydrogen-Exposed 316L Stainless Steel at Ambient and Cryogenic Temperatures

Metals ◽  
2019 ◽  
Vol 9 (6) ◽  
pp. 625 ◽  
Author(s):  
Le Thanh Hung Nguyen ◽  
Jae-Sik Hwang ◽  
Myung-Sung Kim ◽  
Jeong-Hyeon Kim ◽  
Seul-Kee Kim ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Stainless Steel ◽  
Low Temperatures ◽  
316L Stainless Steel ◽  
Charpy Impact ◽  
Cryogenic Temperatures ◽  
Absorbed Energy ◽  
Impact Properties ◽  
Charging Time ◽  
The Impact

316L stainless steel is a promising material candidate for a hydrogen containment system. However, when in contact with hydrogen, the material could be degraded by hydrogen embrittlement (HE). Moreover, the mechanism and the effect of HE on 316L stainless steel have not been clearly studied. This study investigated the effect of hydrogen exposure on the impact toughness of 316L stainless steel to understand the relation between hydrogen charging time and fracture toughness at ambient and cryogenic temperatures. In this study, 316L stainless steel specimens were exposed to hydrogen in different durations. Charpy V-notch (CVN) impact tests were conducted at ambient and low temperatures to study the effect of HE on the impact properties and fracture toughness of 316L stainless steel under the tested temperatures. Hydrogen analysis and scanning electron microscopy (SEM) were conducted to find the effect of charging time on the hydrogen concentration and surface morphology, respectively. The result indicated that exposure to hydrogen decreased the absorbed energy and ductility of 316L stainless steel at all tested temperatures but not much difference was found among the pre-charging times. Another academic insight is that low temperatures diminished the absorbed energy by lowering the ductility of 316L stainless steel.

Effect of Various Welding Parameters on the Mechanical Behaviour of 316L Stainless Steel-Galvanized Steel Weld

2019 ◽  
Vol 969 ◽  
pp. 807-812 ◽  
Author(s):  
P. Shreyas ◽  
Bijayani Panda ◽  
Rakesh Kumar
Keyword(s):  
Stainless Steel ◽  
Impact Strength ◽  
Mechanical Behaviour ◽  
Zinc Coating ◽  
Microstructural Characterization ◽  
Tensile Tests ◽  
Galvanized Steel ◽  
Welding Parameters ◽  
Shielding Gas ◽  
The Impact

Several case studies have shown that welding of stainless steel to galvanized steel leads to evolution of zinc which can penetrate through the steel and result in cracking, the present study focuses on determination of the effect of zinc on the mechanical behaviour of such weld joints. Welding was carried out using two shielding gas combinations. The other variations in parameters were heat input and presence or absence of zinc coating at the weld location. Tensile tests showed that the ductility of weld specimen improved when the coating was stripped off the samples prior to welding. Impact strength of weld specimens also followed similar trend. The impact strength was found to be improved when welding was done using Ar+2%He+2%O2 as shielding gas. The compressive strength was found to be similar. To explain the mechanical behaviour of the welded specimen, microstructural characterization of the weld region was carried out.

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