Suppression of intergranular corrosion by surface grain boundary engineering of 304 austenitic stainless steel using laser peening plus annealing

Optimum parameters in the thermomechanical treatment during grain boundary engineering (GBE) were investigated for improvement of intergranular corrosion resistance of type 304 austenitic stainless steel. The grain boundary character distribution (GBCD) was examined by orientation imaging microscopy (OIM). The intergranular corrosion resistance was evaluated by electrochemical potentiokinetic reactivation (EPR) and ferric sulfate-sulfuric acid tests. The sensitivity to intergranular corrosion was reduced by the thermomechanical treatment and indicated a minimum at a small roll-reduction. The frequency of coincidence-site-lattice (CSL) boundaries indicated a maximum at the small pre-strain. The ferric sulfate-sulfuric acid test showed much smaller corrosion rate in the thermomechanical-treated specimen than in the base material for long time sensitization. The optimum thermomechanical treatment introduced a high frequency of CSL boundaries and the clear discontinuity of corrosive random boundary network in the material, and resulted in the high intergranular corrosion resistance arresting the propagation of intergranular corrosion from the surface.

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Strain-Annealing Based Grain Boundary Engineering to Evaluate its Sole Implication on Intergranular Corrosion in Extra-Low Carbon Type 304L Austenitic Stainless Steel

Metallurgical and Materials Transactions A ◽

10.1007/s11661-018-4608-1 ◽

2018 ◽

Vol 49 (7) ◽

pp. 2817-2831 ◽

Cited By ~ 13

Author(s):

S. K. Pradhan ◽

P. Bhuyan ◽

C. Kaithwas ◽

Sumantra Mandal

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Grain Boundary ◽

Intergranular Corrosion ◽

Grain Boundary Engineering ◽

Low Carbon

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Application of Grain Boundary Engineering to Improve Intergranular Corrosion Resistance in a Fe–Cr–Mn–Mo–N High-Nitrogen and Nickel-Free Austenitic Stainless Steel

Acta Metallurgica Sinica (English Letters) ◽

10.1007/s40195-020-01000-8 ◽

2020 ◽

Vol 33 (6) ◽

pp. 789-798 ◽

Cited By ~ 2

Author(s):

Feng Shi ◽

Ruo-Han Gao ◽

Xian-Jun Guan ◽

Chun-Ming Liu ◽

Xiao-Wu Li

Keyword(s):

Stainless Steel ◽

Corrosion Resistance ◽

Austenitic Stainless Steel ◽

Grain Boundary ◽

Intergranular Corrosion ◽

Grain Boundary Engineering ◽

High Nitrogen ◽

Intergranular Corrosion Resistance

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The Relationship between Grain Boundary Character Distribution and Intergranular Corrosion Resistance of 304 Austenitic Stainless Steel

Materials Science Forum ◽

10.4028/www.scientific.net/msf.689.239 ◽

2011 ◽

Vol 689 ◽

pp. 239-244

Author(s):

Xiao Ying Fang ◽

Xiao Cui ◽

Cong Xiang Qin ◽

Wei Guo Wang

Keyword(s):

Stainless Steel ◽

Austenitic Stainless Steel ◽

Grain Boundary ◽

Intergranular Corrosion ◽

Electron Backscatter Diffraction ◽

Grain Boundary Character Distribution ◽

Surface Appearance ◽

Boundary Character ◽

Grain Boundary Character ◽

304 Austenitic Stainless Steel

A wedge-shaped 304 austenitic stainless steel with varied thickness longitudinally was cold rolled into a flat one and then annealed at 1323K for 10 min. The grain boundary character distributions (GBCDs) in the specimen as processed were examined by the means of Electron backscatter diffraction (EBSD). The results showed that, at the regions with low pre-strains ranged from 4% to 6%, quite high fractions of S3n (n=0,1,2,3) grain boundaries and large-sized S3n (n=0,1,2,3) grain clusters are introduced compared with the regions of quite low ( less than 2.5%) or relatively high pre-strain. The surface appearance of after corrosion test reveals that grain dropping due to intergranular corrosion (IGC) is depressed and the penetration of IGC from the surface into the interior in the cross-section is arrested significantly as well in the regions with high fractions of S3n boundaries and large-sized S3n grain clusters.

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