Process of Forming Ultrafine Crystal Layer, Machine Component Having Ultrafine Crystal Layer Formed by the Ultrafine Crystal Layer Forming Process, Process of Producing the Machine Component, Process of Forming Nanocrystal Layer, Machine Component Having Nanocrystal Layer Formed by the Nanocrystal Layer Forming Process, and Process of Producing the Machine Component

摘要

An ultrafine crystal layer forming process of forming an ultrafine crystal layer in a workpiece constituted by a metallic material. The process includes: 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, where the machining operation using the machining tool causes the machined surface of the workpiece to be subjected to a plastic working that causes to have large local strain in the form of a true strain of at least 1, such that the ultrafine crystal layer is formed in a surface layer portion of the workpiece that defines the machined surface of the workpiece. Also disclosed are a nanocrystal layer forming process, a machine component having the ultrafine crystal layer or the nanocrystal layer, and a machine component producing process of producing the machine component.