熔融沉积制件尺寸规格不同将引起尺寸精度差异性问题，对采用不同评价指标优化工艺参数时会引起错误导向。为此，文中针对 3 种尺寸规格试样，以层厚、填充速度、喷头温度和填充率为因素，以尺寸误差、偏差和打印时间为质量评价指标，采用Taguchi 正交实验法，研究不同尺寸规格与评价指标对熔融沉积工艺参数优化的影响。实验结果表明: 3 种试样沉积时存在尺寸精度差异性，不同组的等效尺寸偏差值和各方向尺寸偏差值呈波浪递增趋势，且前者波动幅度随尺寸规格的增大而减小; 两种精度指标有优劣之分，偏差指标更为科学合理; 由打印时间指标得到的因素影响顺序相同。文中最后对比了因素优水平数据结果，提出了不同质量要求下 3 种试样的工艺参数组合优化方案。

Different dimensions of fused deposition parts cause the differences in dimensional accuracy，which will mislead the optimizing process of parameters by employing different quality assessment indexes． Therefore，three types of samples with different dimensions were tested by the Taguchi orthogonal experiment method，which took layer thickness，filling velocity，nozzle temperature and filling rate as the factors and took dimensional error，dimensional deviation and build time as quality assessment indexes to investigate the influence of different part dimen-sions and assessment indexes on the optimization of fused deposition modeling process parameters． The results show that three types of samples exhibit differences in size accuracy during deposition; curves of both equivalent and each dimensional deviation values of different groups generally present an increasing trend of waves，and the fluctuation range of equivalent dimensional deviation values declines with the increase of the size of samples． Two accuracy assessment indexes are different． The dimensional deviation index are more scientifically reasonable in general，and sequences of factors for evaluating printing efficiency of these samples were the same． Finally，the results of factors＇optimized levels were compared，and the optimization scheme of the combination of process parameters of three samples under different quality requirements was proposed．