The results showed that enwrapping dimple is main style produced in the multi-point stretching process, the dimples can be suppressed effectively when elastic cushion was used.

• 研究结果表明：多点拉形工艺中的压痕主要分为包络式和凹凸式压痕；采用弹性垫技术能够有效抑制压痕的产生；