Sheet metal forming limit research method based on heat-flow multi-field coupling

Abstract

The invention discloses a sheet metal forming limit research method based on heat-flow multi-field coupling. The sheet metal forming limit research method based on heat-flow multi-field coupling is tostudy the forming limit of a sheet metal under a complex strain path by combining preforming at normal temperature with final forming at high temperature with a fluid medium as a force transfer carrier. The research method is defined as follows that in the initial cold preforming stage, an upper die moves downward to be closed with a lower die to press the sheet metal in the middle of the die, ahydraulic control system regulates the working pressure value P of fluid in a liquid chamber, and a sealing device ensures the constant working pressure value, so that the different plastic deformation amount of the sheet metal is achieved; and in the high temperature final forming stage, the hydraulic control system relieves pressure on the liquid chamber to retain the plastic deformation of thematerial, then, a heating device in the upper die is controlled by the temperature control system to achieve the controllable adjustment of the die temperature and ensure the consistency of the temperature between the sheet metal and the die, the fluid pressure continues to increase, the material ruptures and fails, and the test ends. The conclusion of the influence of the pre-deformation amount h0 and the heating temperature T on the forming limit of different materials has a broad application prospect for the development of new materials and new processes.

Description

technical field [0001] The invention belongs to the technical field of sheet metal forming limit, and in particular relates to a research method of sheet forming limit under the coupling action of thermophysical field and flow field. Background technique [0002] Due to the needs of environmental protection and energy saving and emission reduction, the lightweight of automobiles has become the main trend of the world's automobile development. The way to achieve this mainly includes structural lightweight, lightweight materials and integration requirements, among which lightweight metal materials are the most important solution. The method can not only realize weight reduction, but also ensure sufficient use strength, and greatly protect people's life safety. However, most light metal materials have defects such as poor plasticity, low forming limit, and large springback deformation at room temperature. The traditional forming process cannot meet the expected deformation of t...

AI Technical Summary

Problems solved by technology

These problems will not only affect the formulation of specific process routes, but also affect the comprehensive utilization of materials

Images