Patent ID: 8382919
Filing Date: 2013-02-26
Classification: B23B,B23C,B23P,C21D,Y10T

Abstract:
1. A nanocrystal layer forming process of forming a nanocrystal layer in a workpiece constituted by a metallic non-steel material, said process comprising: performing a machining operation on a surface of the workpiece using a machining tool, so as to impart a large local strain to the machined surface of the workpiece, such that said nanocrystal layer is formed in a surface layer portion of the workpiece that defines the machined surface of the workpiece; wherein the machining operation using the machining tool causes the machined surface of the workpiece to be subjected to a plastic working that causes the machined surface of the workpiece to have said large local strain in the form of a true strain of at least 7; and wherein said machining operation is performed on the surface of the workpiece, with a material temperature at the machined surface of the workpiece being held in a range which is not lower than half a melting point of the non-steel material and is lower than the melting point of the non-steel material, where said material temperature and said melting point are expressed in terms of absolute temperature.