在平面应变假设条件下,对轴对称拉深成形法兰区的起皱失稳问题进行了理论分析。首先采用数学方法,将以积分形式表示的应力解析式进行了简化。在此基础上,进一步简化了起皱过程中变形能的计算式。给出的算例表明,对起皱过程中的变形能分别以简化后的计算式和以原积分式进行计算,其结果误差很小,相对误差小于0.8%。该起皱失稳临界压边力的计算和分析简化方法有助于给出简明和符合实际的起皱判据。
In the condition oI the plane strain nypotnems, ilange w~mr.img matau,~,Ly u metal in axisymmetric deep drawing was analyzed theoretically. At first, stress formula in integral form was simplified by mathematical method. On the basis of that, the calculation of the strain ener- gy was simplified. Given examples show that the calculation results by simplified formula are close to that by original integral one. The maximum relative error is less than 0. 8%. Finally, a simplified for- mula for calculation of critical BHF of wrinkling instability was given. It is helpful to provide concise and realistic wrinkling criterion.