基于RSM-BBD的选择性激光烧结制件尺寸补偿预测

Dimensional Compensation Prediction of Selective Laser Sintered Parts based on RSM-BBD

选择性激光烧结(SLS)技术是一种快速成型技术,该技术具有低成本、高效率、高质量等特点。由于传统的补偿算法未能同时考虑扫描线烧结宽度和冷却收缩的影响,这导致尺寸误差的产生。为了更好地控制SLS的打印精度,以聚醚砜(PES)粉末为材料,采用响应面试验设计(RSM-BBD)研究不同工艺参数如预热温度、激光功率、扫描间距、扫描速度4个因素对制件尺寸的影响。建立这4个因素与响应值之间的多项式回归方程。根据工艺参数组合对尺寸补偿进行预测。结果表明,影响因素与响应值呈现二次多项式关系,其回归系数R2大于0.9、R2预测值与R2校正值的差值小于0.2,两者较为接近。信噪比比值大于4,变异系数(CV)小于10%,这说明试验可信度和精确度高。通过响应面分析可知,尺寸补偿预测值和实际测量值的误差皆小于5%。所以该尺寸补偿预测模型具有较高的预测可靠性。基于该预测值对轮廓进行补偿可以提高制件的尺寸精度,为SLS尺寸补偿的研究提供了一定帮助。

Selective laser sintering(SLS)technology is a rapid prototyping technology,which is characterized by low cost,high efficiency and high quality.However,the current compensation algorithm does not take into account the effects of scan line sintering width and cooling shrinkage,leading to dimensional errors.To better control the printing accuracy of SLS,using polyether‐sulfone resin(PES)powder as the test material,the response surface experimental design(RSM-BBD)response surface method was used to study the effects of four factors of different process parameters such as preheating temperature,laser power,scan spacing,and scan speed on the dimensions of the fabricated parts.A polynomial regression equation was established between the four factors and the response values to predict dimensional compensation based on the combination of process parameters.Results indicate that there is a quadratic polynomial relationship between the factors and response values,the regression coefficient R2 is greater than 0.9 and the difference between the predicted and corrected R2 values is less than 0.2.Additionally,the signal-to-noise ratio ratio is greater than 4,and the coefficient of variation(CV)is less than 10%indicating high reliability and accuracy of the test.And the response surface analysis shows that the error between predicted and actual measured values is less than 5%.Therefore,this size compensation prediction model provides high prediction reliability.Compensating the contour based on this predicted value can significantly improve the dimensional accuracy of fabricated parts,thereby aiding in the study of dimensional compensation for SLS.