以三边圆弧形横截面空心零件为研究对象,进行了应变网格实验,获得了旋压件母线方向、周向和厚向的应变分布规律及等效应变分布规律.结果显示:旋压件侧壁和口部的应变状态为母线方向受拉、周向和厚向受压,以母线方向和厚向的应变为主,周向应变很小；侧壁和口部成形时坯料变形方式分别是剪切旋压和以剪切旋压为主、兼有拉深旋压的复合变形；旋压件大小圆锥面侧壁母线方向、厚向应变和等效应变的分布状况一致——从圆角区至口部,应变先增大后减小,但小圆锥面侧壁产生较大应变的区域比大圆锥面大；应变分布主要受变形程度和速度的影响:变形程度的不同导致大圆锥面与小圆锥面之间应变分布不相同；变形速度的变化导致大小圆锥面横截面上应变分布的变化.%As a hollow part with triangular arc-type cross-section is investigated by a strain grid experiment, the distributions of the strain along the generatrix or in the circumferential and the thickness directions and the equivalent strain are obtained. The results show that( 1) the strain of the side wall and the opening area of spun part is tension along the generatrix direction and compression in the other two directions, and the strains along the generatrix and thickness directions are the major ones but the strain in the circumferential direction is the minor one; (2) the deformation modes of the side wall and the opening area during forming are respectively the shear spinning and a complex deformation major in shear spinning but minor in conventional spinning; (3 ) on the sides of both big and small conical walls, the strain along the generatrix and thickness directions first increases and then decreases from the comer to the opening area,which are the same as the equivalent strain, but the zone with large strain on the side of the small conical wall is larger than that of the big conical wall; and (4) the strain distribution is mainly affected by the deformation extent and velocity: the difference in the former results in the strain distribution difference between the big conical wall and the small one; and the variation in the latter causes the strain distribution to vary along the cross-section profile.
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