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Influência do tratamento criogênico na usinabilidade do aço rolamento ABNT 52100 temperado

IV Departamento de Engenharia Mecânica, Universidade Federal de Minas Gerais, Av. Antônio Carlos, 6627, Pampulha, Belo Horizonte, MG
Matéria (Rio de Janeiro) 01/2009; 14(3):932-946. DOI: 10.1590/S1517-70762009000300005

ABSTRACT RESUMO O objetivo deste trabalho é avaliar a influência do tratamento criogênico sobre a usinabilidade do aço rolamento ABNT 52100 temperado e revenido para uma dureza média entre 64 e 65 HRC. Testes de torneamento contínuo a seco foram realizados com ferramentas de corte de alumina mista. Além da influência do tratamento criogênico, o efeito da velocidade de corte e do avanço sobre a vida da ferramenta e acabamento da superfície usinada foi investigado. Não foram encontradas diferenças significativas entre os valores de microdureza das amostras tratadas criogenicamente por 4 e 24 horas e, de uma maneira geral, a amostra tratada por 24 horas apresentou menor rugosidade e propiciou vida mais longa à ferramenta de corte. Finalmente, os índices S bi e S ci indicam que o aço ABNT 52100 tratado por criogenia em 24h apresenta notáveis resultados para aplicações de deslizamento e retenção de filmes lubrificantes. Palavras-chaves: torneamento, aço temperado, tratamento criogênico, ferramenta cerâmica.

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