This work presents the technologies more widely used to improve the machinability of metal materials, mainly focusing on the free-machining steels. A wide literature and patent review are included with the purpose of presenting the state of the art on free-machining steels.
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HayaishiM.Steel for machining structural use excellent in friability of chips. European Patent 1553201A1 (filed 2005).
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FukuzumiT.Sulfur-containing free-cutting steel for machine structural use. US Pat. 7,014,812 (filed 2006).
