Characterization and Corrosion Resistance of Boron-Containing-Austenitic Stainless Steels Produced by Rapid Solidification Techniques

Author(s)

Koga, Guilherme Y. ^{[1, 2]} ; Otani, Lucas B. ^[1] ; Silva, Ana M. B. ^[1] ; Roche, Virginie ^[2] ; Nogueira, Ricardo P. ^{[2, 3]} ; Jorge, Jr., Alberto M. ^{[1, 2]} ; Bolfarini, Claudemiro ^[1] ; Kiminami, Claudio S. ^[1] ; Botta, Walter J. ^{[1, 2]}

Affiliation

^[1] Univ Fed Sao Carlos, Dept Mat Sci & Engn, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Grenoble Alpes, CNRS, UMR5279, LEPMI, Grenoble INP, 1130 Rue Piscine, BP 75, F-38402 St Martin Dheres - France

^[3] Khalifa Univ Sci & Technol, Gas Res Ctr, POB 2533, Abu Dhabi - U Arab Emirates

• Document type: Journal article
• Source: MATERIALS; v. 11, n. 11 NOV 2018.
• Web of Science Citations: 6

Abstract

The composition of a commercial duplex stainless steel was modified with boron additions (3.5, 4.5, and 5.5 wt.%) and processed by rapid-quenching techniques: Melt-spinning, copper-mold casting, and high-velocity oxygen fuel (HVOF). Spray deposition was also used to produce alloys as the process may induce rapid-solidified-like microstructures. These processing routes led to microstructures with distinguished corrosion resistance. Among the alloys with different boron contents, the 63.5Fe25Cr7Ni4.5B composition enabled the production of fully amorphous ribbons by melt-spinning. The cooling rate experienced during copper-mold casting, high-velocity oxygen fuel, and spray deposition did not ensure complete amorphization. The crystalline phases thereby formed were (Fe,Cr)(2)B and (Fe,Mo)(3)B-2 borides in an austenitic-matrix with morphology and refinement dependent of the cooling rates. Fully amorphous 63.5Fe25Cr7Ni4.5B ribbons exhibited outstanding corrosion resistance in chloride-rich alkaline and acid media with negligible corrosion current densities of about 10(-8) A/cm(2) and a broad passivation plateau. Although the specimens of the same composition produced by HVOF process and spray deposition exhibited lower corrosion resistance because of intrinsic porosity and crystalline phases, their corrosion behaviors were superior to those of AISI 1045 steel used as substrate with the advantage to be reinforced with hard borides known to be resistant against wear. (AU)

• FAPESP's process: 17/09237-4 - Design and production of spray-formed boron-modified stainless steels with high corrosion and wear resistance
• Grantee: Guilherme Yuuki Koga
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/05987-8 - Processing and characterization of amorphous, metastable and nano-structured metallic alloys
• Grantee: Claudio Shyinti Kiminami
• Support Opportunities: Research Projects - Thematic Grants