This work presents an experimental and numerical study of process-induced deformation (PID) in flat sandwich panels with in-homogeneous ply layups. An over-expanded Nomex honeycomb core and aerospace-grade prepreg was used to manufacture sandwich panels using the autoclave technique. Process-induced spring-in and warpage at different locations were measured. A 3D FE analysis was performed for the full cure cycle. The FE model successfully captured the shrinkage due to cure, anisotropic and thermo-physical properties of the sandwich structure and tool-part interactions. The computed maximum spring-in values obtained from the FE model were in good agreement with average spring-in values measured experimentally. An overall error of less than 2% was found in the PID of the sandwich panel. The effect of tooling material and core material on PID was also investigated. The numerical results suggest that an aluminum tool and an aluminum core could potentially reduce warpage in the sandwich panel studied.

这项工作提供了一个实验和数值研究，研究了不均匀铺层的平面夹心板的过程诱发变形（PID）。使用超高压Nomex蜂窝芯和航空级预浸料来制造夹心板。测量了在不同位置的过程引起的弹入和翘曲。对整个固化周期进行了3D FE分析。有限元模型成功地捕获了由于三明治结构的固化，各向异性和热物理性质以及工具-零件相互作用引起的收缩。从有限元模型获得的最大弹入值与实验测得的平均弹入值非常吻合。在夹心板的PID中发现总误差小于2％。还研究了模具材料和芯材对PID的影响。数值结果表明，铝制工具和铝芯可以潜在地减少所研究夹芯板的翘曲。