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尽管超塑胀形作为一种金属成形方法正日渐受到世界各国的普遍关注，但对超塑约束胀形理论的研究报道却还很少，尤其对胀形过程的有限元模拟研究就更为罕见。针对这种情况，采用大变形刚粘塑性有限元法模拟了轴对称零件向圆筒形凹模内超塑约束胀形的变形过程，着重研究了工具工件之界面摩擦对胀形件厚度分布不均匀性和胀形板料向凹模角部充填性的影响．结果表明，随着摩擦的降低，胀形件的侧向较厚部分能有所减薄，可以改善整个胀形件的厚度均匀性，但当摩擦因子Ａｍ≤０．２（相当于摩擦系数μ≤０．１２）时，胀形件极顶部分的减薄过大；摩擦较小时，胀形板料向凹模角部的充填性较好；在考虑到极点附近厚度适度减薄和胀形板料对凹模角部充填性好的前提下，工艺上应当适当减小摩擦，其最佳状态是μ值约为０．３．为了检验所用刚粘塑性有限元法模拟的可靠性，将计算结果与试验结果作了对比，发现两者相当吻合。
Although superplastic bulging as a method of metal forming is gaining widespread attention in many countries around the world, there are few reports on the theory of superplastic bulging bulging. In particular, finite element simulation of bulging is more common . In view of this situation, the large deformation rigid viscoplastic finite element method was used to simulate the deformation process of the axially symmetric part to the superplastic constraining bulge in the cylindrical die. The research focused on the relationship between the friction of the work piece and the bulge thickness distribution Uniformity and the influence of bulging sheet material on fillet corner filling. The results show that with the decrease of friction, the thicker lateral part of the bulging part can be thinned and the thickness uniformity of the whole bulging part can be improved. However, when the friction factor Am≤0.2 (corresponding to the friction coefficient μ ≤ 0.12), the bulging of the top part of the thinning is too large; when the friction is small, the bulging of the bulging sheet to the corner of the better filling; taking into account the thickness of the pole in the appropriate thinning and bulging plate Material under the premise of good filling of the corner of the die, the process should be properly reduced friction, the best state is μ value of about 0.3. In order to test the reliability of the rigid visco-plastic finite element method simulation, the calculated results are compared with the experimental results and found that the two are in good agreement.