【摘要】 目的管材差温剪切弯曲成形技术,是实现极小弯曲半径(中心线弯曲半径小于管径)薄壁钛管制造的新型技术。管材的减薄及扁化特性,是实现该过程成形质量精确控制迫切需要解决的关键问题。方法采用实验方法,研究了工艺参数对TA2薄壁钛管差温剪切弯曲过程减薄和扁化的影响。结合响应面法,获得了实验条件下的弯管成形极限。结果管模间摩擦越大,或弯曲行程H越大,或外圆角半径r_o越小,管材减薄和扁化均越大。结论内圆角半径r_i=4.00 mm,外圆角半径r_o=14.15 mm是管材最佳的弯曲半径匹配,H∈[30 mm,32 mm]能够保证管材稳定成形。更多还原

【Abstract】 Tube shear bending technology under differential temperature fields constraints(DTFCs)is a new technology for manufacturing Ti-alloy thin-walled tubes(TATTs)with ultra-small bending radii(tube bending radii<diameters). The thinning and flattening characteristics have become key problems urgently to be solved for improving forming qualities in the shear bending processes under DTFCs of TATTs. The effects of the forming parameters on the thinning and the flattening in these processes of TA2 TATTs were studied using the experimental approach. By combining this approach with the response surface method,the forming limits under the experimental conditions were determined. The larger the friction between the tubes and the dies,the larger the H,or the smaller the r_o,the larger the thinning and the flattening. r_i=4.00 mm,and r_o=14.15 mm were the optimal combination of the bending radii,and H∈[30 mm,32 mm] enabled stable forming of the tube.更多还原