SURFACE STATE EFFECT OF WELDED STAINLESS STEELS ON CORROSION BEHAVIOR

Welding joints of stainless steels are in practice very sensitive places attacked by local corrosion, such as pitting and crevice corrosion, mostly in chloride containing oxidizing environments. It is caused by different oxidation products created on the surface by welding. Corrosion resistance of stainless steels is affected by quality of passive layer (Cr2O3) which created at normal conditions on air. After welding the steels are heated and on the surface are originated different types of oxides which do not have the same protective properties. Resistance to intergranular and pitting corrosion of the welded stainless steels with different surface finishing was tested. Experimental materials are the austenitic stainless steel AISI 316L (welded by the TIG method in inert argon atmosphere with filler) and the ferritic stainless steel AISI CA6-NM (welded by the WPS method in inert argon atmosphere with filler and after welding heat treated). Character of the surface after welding and after finishing by grinding and pickling was evaluated by SEM microscopy, EDX analysis. Corrosion resistance to local forms of corrosion was investigated by electrochemical potentiodynamic test and by exposure tests in chloride solutions. The steel AISI CA6-NM was tested in fluvial water to simulate real operation environment. The evaluation is supported by microscopic analysis. Susceptibility to intergranular corrosion was tested too and results detect the dangerous localities for corrosion attack and show increasing of corrosion resistance by surface treatment.

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AL TECH MIAMI

Alloy Digest ◽

10.31399/asm.ad.ss0435 ◽

1983 ◽

Vol 32 (11) ◽

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Heat Treating ◽

Good Resistance ◽

Aisi Type ◽

Steel Aisi ◽

Resistance To Wear ◽

Specialty Steel ◽

Stainless Steel Aisi ◽

Plastic Mold

Abstract AL TECH MIAMI is both a hardenable stainless steel (AISI Type 420) and a tool steel for making molds for plastic. A major requirement for plastic mold steel is corrosion resistance. Certain plastics, such as poly-vinyl chlorides, are very corrosive and stored molds often rust from sweating water lines and/or humid environments. AL TECH MIAMI has good resistance to wear. It is melted and AOD refined to assure the mold-maker of cleanliness and freedom from internal imperfections. It provides exceptionally good polishability for lens-quality molds. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, and machining. Filing Code: SS-435. Producer or source: AL Tech Specialty Steel Corporation.

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Phase Studies in WC-Stainless Steel AISI 347 Hardmetal System with Graphite Addition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1024.239 ◽

2014 ◽

Vol 1024 ◽

pp. 239-242

Author(s):

Zuhailawati Hussain ◽

Emee Marina Salleh ◽

Tran Bao Trung ◽

Zainal Arifin Ahmad

Keyword(s):

Stainless Steel ◽

Powder Mixture ◽

Milled Powder ◽

Graphite Powder ◽

Planetary Mill ◽

Argon Atmosphere ◽

Maximum Hardness ◽

Steel Container ◽

Steel Aisi ◽

Stainless Steel Aisi

In this study, WC-stainless steel AISI 347 hardmetal system was produced to replace WC-Co hardmetal which uses the expensive, toxic and depleted resource Co. WC, stainless steel AISI 347 and graphite powder mixture were milled in a planetary mill under argon atmosphere using a stainless steel container and balls. Carbon was added in amounts ranging from 0 wt% until 4 wt% into the composition to avoid unwanted η (Fe3W3C) phase. As-milled powder was compacted at 300 MPa and sintered in a tube furnace at 1350°C. ɳ phase was detected in compositions with 0 and 1 wt% C addition. For 2 wt% C addition, no η (Fe3W3C) phase formation was identified. However, the η phase was detected for compositions containing 3 and 4 wt% C. Maximum hardness was achieved due to the absence of η phase.

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Effects of Heat Treatment on Phase Transformation and Corrosion Resistance of Boride Layer on Austenitic Stainless Steel AISI 304

Metallurgical and Materials Transactions B ◽

10.1007/s11663-018-1337-1 ◽

2018 ◽

Vol 49 (5) ◽

pp. 2875-2880 ◽

Cited By ~ 5

Author(s):

P. Naemchanthara ◽

P. Juijerm

Keyword(s):

Heat Treatment ◽

Stainless Steel ◽

Corrosion Resistance ◽

Phase Transformation ◽

Austenitic Stainless Steel ◽

Boride Layer ◽

Aisi 304 ◽

Steel Aisi ◽

Stainless Steel Aisi

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Corrosion Behavior of Construction Materials for Intermediate Temperature Steam Electrolysers

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.699.596 ◽

2013 ◽

Vol 699 ◽

pp. 596-605 ◽

Cited By ~ 4

Author(s):

Aleksey V. Nikiforov ◽

Irina M. Petrushina ◽

Jens Oluf Jensen ◽

Niels J. Bjerrum

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Construction Materials ◽

Intermediate Temperature ◽

Aisi 316L ◽

Corrosion Stability ◽

Metal Phosphates ◽

High Corrosion ◽

Steel Aisi ◽

Stainless Steel Aisi

Different corrosion resistant stainless steels, nickel-based alloys, pure nickel, Ta-coated stainless steel (AISI 316L), niobium, platinum and gold rods were evaluated as possible materials for use in the intermediate temperature (200-400 °C) acidic water electrolysers. The corrosion resistance was measured under simulated conditions (molten KH2PO4) corresponding to the proton-conducting solid acids or transition metal phosphates as electrolytes. It was shown that, unlike at temperatures below 200 °C, gold is unstable with respect to corrosion in molten KH2PO4. Platinum demonstrated high corrosion resistance and the anodic and cathodic limits were for the first time found for the electrolyte. Nickel, niobium, Inconel®625, Hastelloy®C-276 and Ta-coated stainless steel (AISI 316L) demonstrated high corrosion stability and can be recommended as construction materials for bipolar plates.

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Stainless steel corrosion in instrumentation pipe

Cadernos UniFOA ◽

10.47385/cadunifoa.v14.n40.2940 ◽

2019 ◽

Vol 14 (40) ◽

pp. 31-40

Author(s):

Jean Victal do Nascimento ◽

Rafael Adão de Carvalho ◽

Davi Pereira Garcia ◽

Rômulo Maziero ◽

Edelize Angelica Gomes ◽

...

Keyword(s):

Stainless Steel ◽

Chemical Composition ◽

Austenitic Stainless Steel ◽

Stainless Steels ◽

Chloride Ions ◽

Main Function ◽

Marine Atmosphere ◽

Steel Aisi ◽

Aisi 316 ◽

Stainless Steel Aisi

Corrosion, being a destructive process, causes damage in almost all industrial sectors. In this way, it is harmful both from an economic, social and, especially, safety point of view, as it can cause failures in critical equipment and components of an industrial process. At this point, stainless steels are considered the most corrosion resistant metals. The resistance depends on the chemical composition and microstructure, factors that directly influence the passivation of these materials. The resistance is proportionally related to the addition of chromium (Cr) to the mixture, as well as other alloying elements, among which is the molybdenum (Mo), whose main function is to maximize corrosion resistance in the marine atmosphere, as in case of austenitic stainless steel AISI 316 which presents in the chemical composition a percentage of the element Mo. Austenitic stainless steels are applied in instrumentation systems in tubing for reliability in severe atmospheres in accordance with ASTM A269 which establishes the materials applicable to this function. Thus, the present work presents, through a review and case study, Pitting Corrosion of tubings of austenitic stainless steel AISI 316 in the presence of chloride ions (Cl-) coming from the marine atmosphere. The results show that there is no change in the longitudinal and transverse structure for all analyzed tubes, showing a homogeneous austenitic structure, free of intergranular precipitations.

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Effect of Electrolyte on the Surface Smoothness Obtained by Electropolishing of Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.713.55 ◽

2012 ◽

Vol 713 ◽

pp. 55-60 ◽

Cited By ~ 4

Author(s):

M. Hernando ◽

Pedro Jose Núñez López ◽

Eustaquio García Plaza ◽

R. Trujillo

Keyword(s):

Stainless Steel ◽

Surface Finish ◽

Chromic Acid ◽

Bath Temperature ◽

Surface Finishing ◽

Initial Surface ◽

Surface Finishes ◽

Finishing Process ◽

Steel Aisi ◽

Stainless Steel Aisi

Electropolishing is a surface finishing process of metals and alloys that enhances brilliant surface finishes with low surface roughness values. The most widely used electrolytes for the electropolishing of stainless steel are varying concentrations of phosphoric and sulphuric acid, and occasionally additives such as chromic acid. The objective of this study was to assess the performance of three commonly used industrial electrolytes in terms of the surface finish of electropolished stainless steel AISI 316L. Each electrolyte had varying sulphuric-phosphoric acid combinations with or without chromic acid. The following electropolishing conditions were assessed: current density, bath temperature, electropolishing time, and initial surface texture. The results revealed that adding chromic acid to the electrolyte did not significantly enhance surface finish, and electropolishing ranges were quite similar for all three electrolytes.

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Effect of the Post-Weld Surface Condition on the Corrosion Resistance of Austenitic Stainless Steel AISI 304

Biuletyn Instytutu Spawalnictwa ◽

10.17729/ebis.2018.1/2 ◽

2018 ◽

Vol 2018 (1) ◽

pp. 17-23 ◽

Cited By ~ 1

Author(s):

Grzegorz Rogalski ◽

Mateusz Jurkowski ◽

Jerzy Łabanowski ◽

Dariusz Fydrych

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Austenitic Stainless Steel ◽

Surface Condition ◽

Aisi 304 ◽

Steel Aisi ◽

Stainless Steel Aisi

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Characterization and Corrosion Behavior of Multilayer [TiN/TiCN]n Growth on AISI 316LVM Steel

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.598.13 ◽

2014 ◽

Vol 598 ◽

pp. 13-17

Author(s):

William Aperador ◽

Mauricio Plaza Torres ◽

Erika Ruiz

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Morphological Characterization ◽

Multilayer Coatings ◽

Spatial Period ◽

Silicon Substrates ◽

Tafel Polarization ◽

Steel Aisi ◽

Aisi 316 ◽

Stainless Steel Aisi

In this paper a study of the corrosion resistance is shown in a physiological medium of multilayer coatings [TiN/TiCN] n with periods bilayers of 1, 50 and 150 deposited on silicon substrates ( 100 ) and stainless steel AISI 316 LVM by the method of RF magnetron reactive sputtering with an RF power ( 13.56 MHz ) and using two targets of Ti and TiC. The electrochemical behavior simulated body environment was evaluated by the technique of using Tafel polarization curves, in Hanks solution as electrolyte. Morphological characterization was performed using scanning electron microscopy (SEM) on silicon substrates (100), also was used to characterize the mechanism of attack on the uncoated steel and coated steels. Was found to be markedly increased corrosion resistance to the deposition of multilayer coatings evidencing the effect of the spatial period ( Λ ) in reducing the degradation of these coatings , the effect was shown for the substrate alloy type stainless steel AISI 316 LVM, confirming the good performance of the variation of the bilayers period.

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