非均匀温度场下管材轴压失稳起皱行为的影响因素

To reveal the instability and wrinkling mechanism of tubes under the non-uniform temperature field, the experiments were conducted on 5052 aluminum alloy tube blanks to study the influence of temperature field, internal supporting pressure, axial compression amount and axial compression speed on the shape and thickness distribution of the wrinkle. The results show that axisymmetric wrinkles can be formed under axial compression when the wrinkling temperature reaches 200 ℃ and above. The wrinkle shape can be accurately described by GaussAmp function, and the degree of fitting is higher than 0.99. As the temperature increases, the wrinkle height gradually increases. The higher the internal supporting pressure, the larger the wrinkle width of half height. With the same internal supporting pressure, increasing the axial compression amount can reduce the wrinkle width of half height and increase the height. In addition, the compression speed has little effect on wrinkle shape. When there is no internal supporting pressure, thickening is the largest at the wrinkle peak, followed by the wrinkle valley and it is the least at the wrinkle center. When there is internal supporting pressure, the wall thickness of wrinkle with the internal pressure of 5.5 MPa is the most uniform.