Functionally graded aluminum reinforced with quasicrystal approximant phases - Improving the wear resistance at high temperatures

Autor(es)

Ferreira, Tales ^[1] ; Koga, Guilherme Yuuki ^[2] ; de Oliveira, Ivanir Luiz ^[3] ; Kiminami, Claudio Shyinti ^[2] ; Botta, Walter Jose ^[2] ; Bolfarini, Claudemiro ^[2]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Programa Posgrad Ciencia & Engn Mat, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Fed Sao Carlos, Dept Engn Mat, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil

^[3] Univ Tecnol Fed Parana, Programa Posgrad Engn Mecan, Ave Monteiro Lobato Km 04, S-N, BR-84016210 Ponta Grossa, Parana - Brazil

• Tipo de documento: Artigo Científico
• Fonte: WEAR; v. 462, DEC 15 2020.
• Citações Web of Science: 0

Resumo

Functionally graded aluminum was produced and displayed two well-defined metallurgically bonded layers (A and B). Layer A exhibited a ductile Al-matrix (70 HV0.01) reinforced by 53.4 vol% of hard quasicrystal approximant alpha-Al-12(Fe,Mn,Cr)(3)Si phase (909 HV0.01) distributed homogeneously. Layer B presented the typical structure of a hypoeutectic Al-Si alloy. The tribological behavior of both layers was evaluated in sphere-on-plate configuration at different temperatures: room-temperature, 100, 200, and 300 degrees C. At room temperature, layer A ensured low coefficient of friction values around 0.2. These values were comparable to those of fully quasi crystalline coatings under dry-sliding testing conditions. The specific wear rate at room temperature of the layer A was about one order of magnitude lower than that of the layer B (1.2 x 10(-4) versus 2.7 x 10(-3) mm(3)/Nm, respectively), and three orders of magnitude lower at 300 degrees C (2.3 x 10(-5) versus 2.8 x 10(-2) mm(3)/Nm, respectively). Improved wear resistance and low friction of layer A were achieved through the formation of a protective and compacted Al-rich oxide layer, where the quasicrystal approximant phase played a critical role. The present results and the discussed wear mechanisms provide significant insights into the development of novel alloys for service in critical components. (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