选区激光烧结工艺成型不受制件形状限制，能够成型复杂结构的零件，广泛应用于快速原型制造和新产品设计开发，而探究其成型尺寸精度尤为重要。针对薄壁壳体零件打印尺寸精度低、形状精度不高的问题，提出了基于零件特征的预处理和预补偿提高打印精度的方法。以聚苯乙烯为原料，仿真与实验相结合，采用添加支撑和偏置余量的方法对容易翘曲变形的特征尺寸进行修正以补偿变形，同时调节激光参数改善打印过程中的聚热。对打印结果进行验证，结果表明：相同工艺条件下，零件几何特征的改变直接影响零件的尺寸精度，对零件特征进行添加支撑设置和预变形补偿后，打印件与三维数模比对检测效果良好，实际误差基本能控制在0.3 mm以内。

Selective laser sintering technology is not limited by the shape of the parts, and can form parts with complex structures. Selective laser sintering technology is widely used in rapid prototyping manufacturing and new product design and development. It is particularly important to explore the dimensional accuracy of its forming. Aiming at the problem of low dimensional accuracy and shape accuracy of thin-walled shell parts, this paper proposes a method of preprocessing and precompensation based on part features to improve printing accuracy. Taking polystyrene as raw material, under the combination of simulation and experiment, in order to compensate the deformation, the method of adding support and offset margin is used to correct the feature size, which is easy to warp and deform, and the laser parameters are adjusted to improve the heat accumulation in the printing process. By verifying the printing results, the results show that under the same process conditions, the change of the geometric features of the part directly affects the dimensional accuracy of the part. After adding support settings and predeformation compensation to the part features, the printed parts are compared with the 3D model with good detection results, and the actual error can basically be controlled within 0.3 mm.