| 摘要 |
PURPOSE:To reform structure at irradiated part and to freely adjust the hardness, magnetic permeability, etc., thereof by irradiating high energy density beam on the aimed surface of structural member with steel, etc., under optional beam condition. CONSTITUTION:The necessary part of the structural member 1 made of steel, etc., is irradiated with the high energy density beam 2 of electron beam, etc. In case the matrix 3 of the structural member is the mixed structure of pearlite and bainite, the beam 2 is stopped down and by focusing to the part 4 to be reformed, the structure at the irradiated part 4 is made to martensite by heating at high temp. with the irradiation and rapidly cooling after that, to improve the hardness and the magnetic permeability. Further, in case the material 3 is the martensite structure, by taking off the focus of the electron beam 2, reversely, it can be changed to the bainite structure. By this method, the necessary part of the matrix is locally reforming-treated with adjustment of beam current, voltage, reforming drift velocity, beam oscillating amplitude, frequency, focus position, etc., of the irradiated high energy density beam. |
