Tratamentos Térmicos

PROCESSO DE DESIDROGENAÇÃO PROVOCADO POR ZINCAGEM ELETROLÍTICA
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procedimento:
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minutos a 2 horas.
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PATENTEAMENTO
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dessa alta resistência, apresentam tão boas ductilidade e tenacidade que podem ser enrolados em torno de
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RECOZIMENTO
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ESFEROIDIZAÇÃO
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usinabilidade de aços de alto teor de carbono.
A esferoidização, originando a esferoidita (cementita globular), dá como resultado uma dureza muito
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NORMALIZAÇÃO
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incoveniente.
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REVENIDO
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excessivas dureza e fragilidade do material, aumentando sua ductilidade e resistência ao choque.
A quebra prematura de mola temperada provêm de seu baixo alongamento, que não permite escoa@
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As molas fabricadas a partir de aços carbono laminados a quente ou recozidos exigem têmpera e
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ALÍVIO DE TENSÕES
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, essas cores aparecem em temperaturas mais elevadas, conforme seu grau de inoxidabilidade.
A tabela abaixo, dá uma relação aproximada entre a temperatura e a coloração correspondente.
Amarelo Claro
220ºC
Amarelo Ouro
240ºC
Pardo Avermelhado 260ºC
Roxo
280ºC
Azul
300ºC
Azul Claro
320ºC
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TÊMPERA
A têmpera consiste em resfriar o aço, a partir de uma temperatura de austenitização, a uma velocidade
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alto, devido ao resfriamento drástico e pela brusca mudança de fases, então imediatamente após a têmpera, é
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