Method for quickly and accurately confirming friction coefficient in metal forming processes

Abstract

The invention relates to the field of metal forming manufacturing, in particular to a method for quickly and accurately confirming friction coefficient in metal forming processes. The method comprises n groups of ring upsetting tests: a first group of ring upsetting tests contain three samples, the dimensional proportion of the outer diameter, the inner diameter and the height of a ring sample is 3:2:1, the press-down rate is smaller than 50%, the inner diameter, the outer diameter and the height of the deformed ring sample is measured, each size is measured from three different directions and obtained from the average, the average inner diameter, the outer diameter and the height of the three samples are calculated, the radius of a neutral layer is calculated, friction factor m is calculated, and the best friction factor mi is obtained by calculation. The method is simple and practical, and simultaneously takes bulging and material hardening in the ring sample upsetting test into consideration. Thus, the defect that an existing analytic method cannot simultaneously take bulging and material hardening into consideration is overcome, and complex data processing caused by using a rating curve method is avoided.

Description

technical field [0001] The invention relates to the field of metal plastic processing, in particular to a method capable of quickly and accurately determining the friction coefficient of metal in the plastic forming process. Background technique [0002] Metal plastic processing is carried out under the condition that the tool is in contact with the workpiece. At this time, frictional force that prevents the flow of metal must be generated. This kind of friction that occurs between the contact surface of the workpiece and the tool and hinders the flow of metal is called external friction. Due to the effect of friction, the tool is worn and the workpiece is scratched; the metal deformation force can increase and cause uneven metal deformation; in severe cases, the workpiece will crack, and the tool must be replaced regularly. Therefore, in plastic processing, it is necessary to study the coefficient of friction, to study the friction force, and to lubricate. [0003] The fr...

AI Technical Summary

Problems solved by technology

These methods improve the accuracy to a certain extent, but cannot consider the hardening behavior of the material during plastic deformation, and still need to make a calibration curve

Some domestic experts use the numerical simulation technology of elastic-plastic material model to determine the friction coefficient, which can consider the drum shape and the hardening behavior of metal plastic deformation when the ring is upset, but still need to make a calibration curve

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