Improving the quality of centrifugal cast pipes made of austenitic stainless steel

Users impose increased requirements for companies, which produce equipments used in energy industry, because none of them can afford to loss of production at using of these equipments. The same situation is at gas turbines. Engineers carefully pay attention for every detail – the components go through a strict quality control. The burr formation, as an accompanying phenomenon strongly influences the quality of production. The deburring process effects also the economic characteristics. This article describes the possibility of deburring of a component which is used for gas turbines, The article shows results from carried out studies and described the possibility of by describing of results from brushing process.

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Effect of a continuous and gas-cyclic plasma nitriding on the quality of nanostructured austenitic stainless steel

Metal Working and Material Science ◽

10.17212/1994-6309-2017-2-55-66 ◽

2017 ◽

pp. 55-66 ◽

Cited By ~ 3

Author(s):

Aleksei Makarov ◽

◽

Nikolai Gavrilov ◽

Galina Samoylova ◽

Aleksandr Mamaev ◽

...

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Plasma Nitriding

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Effects of Shielding Gas Pureness on Quality of Orbital TIG Welded Austenitic Stainless-Steel Joints

Materials Science Advanced Composite Materials ◽

10.18063/msacm.v3i1.981 ◽

2019 ◽

Vol 3 (1) ◽

Author(s):

Jacek Górka ◽

Bernard Wyględacz ◽

Marcin Żuk

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Flow Rate ◽

Gas Flow ◽

Welded Joint ◽

Relative Pressure ◽

Delta Ferrite ◽

Additional Material ◽

Technology Institute

Aim of this research was determination of effects of shielding and backing gas pureness on quality of welded joints produced from austenitic stainless-steel grade X5CrNi18-10 (1.4301) pipes Ø 50.8 x 1.5 mm by orbital TIG welding without use of additional material. In the case of stainless steel, it is of importance not only to prepare shielding of the molten metal pool but as well protection of welded joint root from oxygen, which causes formation of colorful oxide layers. Presence of oxidized layer primarily decreases corrosion resistance of stainless-steel. Performed examination included: chemical composition of welded join material, delta ferrite testing, non-destructive joint testing, visual testing with discoloration assessment from face and root side (acc. to Danish Force Technology Institute report 93.34 and American ASME BPE-2012 norm), radiographic testing, destructive welded joint testing. Metallurgical shielding of the welded joint face was produced with Argon 5.0 pure, with a flow rate of 8 dm3/min. Root of welded joint was at first protected with Argon 5.0 pure, then argon-atmospheric air mixtures were used. Backing gas flow rate was set to achieve a relative pressure of 300 Pa. Quantity of residual oxygen in gas mixture was selected based on Danish Force Technology Institute report 93.34.

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Microstructure-Property Relationships in Powder Bed Fusion of Type 304L Austenitic Stainless Steel

Volume 6A: Materials and Fabrication ◽

10.1115/pvp2018-84901 ◽

2018 ◽

Author(s):

Chris San Marchi ◽

Joshua D. Sugar ◽

Thale R. Smith ◽

Dorian K. Balch

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Tensile Properties ◽

Bulk Material ◽

Powder Bed Fusion ◽

Powder Bed ◽

Relative Porosity ◽

Near Net Shape ◽

Properties Of Materials

Additive manufacturing (AM) includes a diverse suite of innovative manufacturing processes for producing near-net shape metallic components, typically from powder or wire. Reported mechanical properties of materials produced by these processes varies significantly and can usually be correlated with the relative porosity in the materials. In this study, relatively simple test components were manufactured from type 304L austenitic stainless steel by powder bed fusion (PBF). The quality of the components depends on a host of manufacturing parameters as well as the characteristics of the feedstock. In this study, the focus is the bulk material response. Tensile properties are reported for PBF type 304L produced in similar build geometries on two different machines with independent operators. Additionally, the effect of hydrogen on the tensile properties of the AM materials is evaluated. The goal of this study is to provide a benchmark for tensile properties of PBF 304L material in the context of wrought type 304L, and to make a preliminary assessment of the effects of hydrogen on tensile properties.

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Analysis of the Causes of Cracks in the Production of Ingots and Forgings from Austenitic Stainless Steel 08Х18Н10Т (AISI 321)

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.854.16 ◽

2020 ◽

Vol 854 ◽

pp. 16-22 ◽

Cited By ~ 3

Author(s):

Artem D. Davydov ◽

Olga O. Erokhina ◽

Sergey Vladimirovich Ryaboshuk ◽

Pavel Valer'evich Kovalev

Keyword(s):

Stainless Steel ◽

Statistical Analysis ◽

Austenitic Stainless Steel ◽

Stainless Steels ◽

Austenitic Stainless Steels ◽

Main Process ◽

Steel Grades ◽

Aisi 321 ◽

Quality Of Products

Austenitic stainless steels are widely used in industry. Increased requirements for the quality of products from these steel grades, the difficulties associated with the implementation of technological processes, as well as the high cost of steel, determine the necessity to assess probable causes of defects. This article presents an analysis of the influence of main process parameters on the quality of products from the grade 08X18H10T steel. Based on the results of statistical analysis and thermodynamic modeling, it was concluded that the increased content of titanium and nitrogen affects the quality of products, which is caused by the formation of titanium carbonitrides in the process of steel solidification.

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Surface Polishing of Plasma Carburized Austenitic Stainless Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.391-392.672 ◽

2011 ◽

Vol 391-392 ◽

pp. 672-676

Author(s):

Shao Mei Zheng ◽

Cheng Zhao

Keyword(s):

Thin Film ◽

Surface Roughness ◽

Stainless Steel ◽

Corrosion Resistance ◽

Austenitic Stainless Steel ◽

Surface Hardness ◽

Surface Appearance ◽

Surface Polishing ◽

Aisi 316

After being plasma carburized, the surface of AISI 316 austenitic stainless steel was covered with a layer of compact black thin-film. The surface polishing treatment, electrochemical brightening was carried out to remove the black thin-film and renew the original color of the stainless steel. The surface appearance, microstructures, micro hardness, surface roughness and corrosion resistance of the samples treated by electrochemical brightening process were analyzed. Experimental results show that the electrochemical brightening treatment can remove the black thin-film from and restore the original color of the plasma carburized stainless steel. After electrochemical brightening treatment, the thickness and surface hardness of the carburized layer were all decreased little, but the corrosion resistance was improved significantly. And the surface roughness (Ra) was lower than before. Therefore, the electrochemical surface brightening treatment can be used to improve the surface quality of the austenitic stainless steel treated by plasma carburizing.

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Some aspects of the defect structure in an austenitic stainless steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108714 ◽

1978 ◽

Vol 36 (1) ◽

pp. 314-315

Author(s):

R. Gonzalez ◽

L. Bru

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Cellular Structures ◽

Total Strain Amplitude ◽

Total Deformation ◽

Density Of Dislocations ◽

Planar Arrays ◽

Stacking Fault Tetrahedra ◽

Distribution Of Dislocations ◽

Very High

The analysis of stacking fault tetrahedra (SFT) in fatigued metals (1,2) is somewhat complicated, due partly to their relatively low density, but principally to the presence of a very high density of dislocations which hides them. In order to overcome this second difficulty, we have used in this work an austenitic stainless steel that deforms in a planar mode and, as expected, examination of the substructure revealed planar arrays of dislocation dipoles rather than the cellular structures which appear both in single and polycrystals of cyclically deformed copper and silver. This more uniform distribution of dislocations allows a better identification of the SFT.The samples were fatigue deformed at the constant total strain amplitude Δε = 0.025 for 5 cycles at three temperatures: 85, 293 and 773 K. One of the samples was tensile strained with a total deformation of 3.5%.

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