The Effect of Cr Content on the Glass Forming Ability of Fe68-xCrxNb8B24 (x =8,10,12) Alloys

• Autor(a) principal: Mendes,Marcio Andreato Batista
• Data de Publicação: 2016
• Outros Autores: Melle,Ana Karla, Souza,Carlos Alberto Caldas de, Kiminami,Claudio Shyinti, Cava,Régis Daniel, Bolfarini,Claudemiro, Botta Filho,Walter José
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Materials research (São Carlos. Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S1516-14392016000700092
• topic: Bulk metallic glasses; Glass forming ability; Rapid-solidification processing; Fe-based alloys

Based on the Fe60Cr8Nb8B24 alloy, reported in the literature as good Glass Forming Ability (GFA), in this study the GFA of two new compositions was proposed, Fe68-xCrxNb8B24 (x=10,12). They were evaluated as good candidates to be new compositions of Bulk Metallic Glasses (BMG) with better corrosion resistance due to the high Cr content. Rapidly solidified glassy ribbons were processed, and based on their thermal characteristics, the critical thickness of the glassy structure formation (Zc) was estimated. The critical thickness (Zc) obtained experimentally using the wedge-shaped casting method was evaluated and it presented a much lower value than that estimated theoretically. However, the GFA of the compositions analyzed was ranked and this ranking (i.e. whichever has the most or least GFA) is in agreement with the result predicted theoretically. The GFA of Fe58Cr10Nb8B24, which presented a maximum thickness of the amorphous region of wedge-shaped samples of about 0.6 mm (but estimated it would be 3.56 mm), offered good prospects to be a new Fe-based glass former alloy which has better resistance to corrosion than the Fe60Cr8Nb8B24 alloy reported.