METHOD FOR MECHANICAL PROCESSING OF AUSTENITIC CLASS STEEL BLANK WITH CHIP CRUSHING Russian patent published in 2023 - IPC B23B1/00 

FIELD: mechanical processing.

SUBSTANCE: invention is intended for the processing of steels of the austenitic class. The method of mechanical treatment of a steel billet with chip crushing includes preliminary preparation of the machined surface by thermal action on the depth of the allowance to be removed. Preliminary preparation is carried out along a straight path parallel to the axis of the workpiece at right angles to the surface being treated by local cryogenic continuous exposure to liquid nitrogen under pressure from 0.2 MPa to 0.5 MPa and temperature from -120 to -130°C. A contact patch with a diameter d_p ensures structural transformations and phase transitions in austenitic steel to a depth of 0.3 to 0.5 of the allowance being removed and forms a metastable structure from which the metal layer is removed with a cutting tool to a cutting depth t_p, which should exceed depth of the metastable structure. The frequency of intersections of the cutting plane with the zone of local cryogenic impact f_m is determined based on the diameter of the workpiece D_w, the required cutting speed V_c m/min and the length of the formed segments L_str straight chips by the dependence f_m = π D_w n_w / 60 L_str ξ = 1000 V_c / 60 L_str ξ.

EFFECT: increased reliability of crushing of drain chips during machining of austenitic stainless steels.

1 cl, 7 dwg