The springback effect in molded wood laminations within the elastic range has, to date, not yet been mathematically described. Once cured, residual internal stresses within the laminations cause the final form to deviate from that of the die. Test pieces of beech laminations of 1 mm, 2 mm and 4 mm thicknesses and stack sizes of between 2 and 16 laminations were used. The elasticity value of each stack was obtained using non-glued laminations in a three-point bending test within the elastic region. The laminations were glued with polyurethane resin and mounted in a radius form die. The stress induced by the die onto the stack is within the elastic region of the material without any prior chemical or physical plasticisation of the wood. After curing was complete and the laminations removed from the die, the actual radius was calculated using a circular equation within the CAD program, using three measurement points taken from the stack. The radius of the die within the limits of this study has a negligible effect when predicting the springback of the stack. The exponential correlation between springback and the number of laminations, was used to calculate the springback effect on molded laminated stacks.

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计算在弹性范围内成型的层压山毛榉堆栈回弹的数学解决方案

迄今为止，尚未在数学上描述弹性范围内的模制木叠片中的回弹效应。固化后，叠层内部的残余内部应力会导致最终形式偏离模具的形式。使用厚度为1 mm，2 mm和4 mm的山毛榉层压板的测试件，堆叠尺寸为2到16个层压板。在弹性区域内的三点弯曲测试中，使用非粘合叠层获得每个叠层的弹性值。叠层用聚氨酯树脂胶粘并安装在圆角模具中。模具引起的施加到叠层上的应力在材料的弹性区域内，而木材没有任何预先的化学或物理增塑。固化完成并将叠层从模具中取出后，实际半径是使用CAD程序中的圆方程，使用从堆栈中获取的三个测量点来计算的。在预测叠层回弹时，模具半径在此研究范围内的影响可忽略不计。回弹与叠片数之间的指数相关性，用于计算回弹对模压叠层堆的影响。