Wear Resistant Duplex Stainless Steels Produced by Spray Forming

Autor(es)

Soyama, Juliano ^{[1, 2]} ; Lopes, Thiago Pama ^[1] ; Zepon, Guilherme ^[1] ; Kiminami, Claudio Shyinti ^[1] ; Botta, Walter Jose ^[1] ; Bolfarini, Claudemiro ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos UFSCar, Dept Engn Mat DEMa, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Estadual Campinas UNICAMP, Fac Engn Mecan, BR-13565905 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: METALS AND MATERIALS INTERNATIONAL; v. 25, n. 2, p. 456-464, MAR 2019.
• Citações Web of Science: 3

Resumo

In this work, boron-modified duplex stainless steels were prepared by spray forming using design guidelines provided by thermodynamic calculations. Firstly, an investigation of stable phases and phase formation sequence in duplex steels containing high levels of boron was conducted. The calculation indicated that there was an eutectic point at around 1wt% boron with different primary phase formations upon equilibrium solidification. For hypoeutectic compositions, the primary phase was -Ferrite, whereas for hypereutectic a metallic boride (M2B) should form. Additionally, eutectic reactions for both compositions should lead to the formation of borides M2B and M3B2. Secondly, spray forming experiments were conducted based on the thermodynamic calculations. Sample preparation was carried out using a conventional superduplex steel (2507) as starting material. Two different compositions were selected: one hypoeutectic (0.8wt% B) and one hypereutectic (2.5wt% B). The microstructural investigation revealed the formation of different types of borides embedded in an austenitic-ferritic matrix. Finally, the wear resistance was evaluated with the dry sand/rubber wheel test and a significant improvement was observed for boron-containing steels in comparison with the same steel without boron. This improvement was attributed to the presence of fine and well-distributed boride particles that protected the austenitic-ferritic matrix from material removal. (AU)

• Processo FAPESP: 13/05987-8 - Processamento e caracterização de ligas metálicas amorfas, metaestáveis e nano-estruturadas
• Beneficiário: Claudio Shyinti Kiminami
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 14/27073-0 - Estudo de aços inoxidáveis modificados com boro e nitrogênio visando a obtenção de materiais resistentes ao desgaste e com baixo coeficiente de atrito
• Beneficiário: Juliano Soyama
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado