Обеспечение качества поверхностей осесимметричных деталей при высокоскоростной вытяжке

Abstract

Для оценки возможности вытяжки листовых изделий без потери устойчивости был проанализирован процесс высокоскоростного деформирования заготовок. Установлено, что процесс получения качественных деталей связан с регулированием скорости разгона штампуемого рельефа и фланцевой части заготовки за счет искусственного увеличения радиуса закругления у перетяжного ребра матрицы. На экспериментальном основании получена эмпирическая зависимость относительного радиуса закругления ребра матрицы от коэффициента вытяжки, что позволяет проектировать технологический процесс высокоскоростного формообразования.

To assess the possibility of drawing sheet products without loss of stability, the process of high-speed deformation of blanks was analyzed. Experiments show that the end of the flange acceleration period for thin sheet stamping coincides with the design of the work piece into a spatial semi-finished product whose depth of punching depends linearly on the radius of curvature of the constr iction of the matrix. If the value of the radius of curvature is less than optimal, further preampling of the semi-finished product is carried out due to the prevailing stretching of the material of the bottom part of the workpiece. It is established that the process of obtaining qualitative details is related to the regulation of the speed of acceleration of the stamped relief and the flange part of the workpiece due to an artificial i ncrease in the radius of curvature at the perimeter of the matrix. On the experimental basis, an empirical dependence of the relative radius of the curvature of the edge of the matrix on the drawing coefficient is obtained, which allows designing the technological process of high-speed shaping. Experimental studies have shown that the corrugations on the surface that arise during stamping with increased radii of curvature, as compared with the usual ones, do not exceed the maximum permissible values when they are eliminated under conditions of biaxi al stretching.