复合材料薄板斜接式挖补修理稳定性优化设计

Optimal Stability Design of Scarf Repaired Laminated Composites

对复合材料层合板挖补修理模型进行了稳定性优化分析。采用ARSM优化算法研究了挖补修理结构失稳载荷与挖补角、胶层厚度以及补片材料与母板材料匹配对挖补修理后复合材料薄板失稳载荷大小的影响,得到了各母板材料对应的稳定性最优挖补修理模型。结果表明,补片材料各方向上的模量匹配非常重要,硼纤维层合板的6个方向上模量搭配最优,硼纤维层合板补片为各个修理方案中的最佳补片材料。当胶层厚度和挖补角参数增大时,失稳载荷逐渐增大,在挖补角与胶层厚度最佳匹配范围内,失稳载荷很快达到最大。在挖补角与胶层厚度脱离最佳匹配范围内后,失稳载荷迅速减小,进一步说明ARSM优化算法可以高效地完成挖补修理结构的稳定性优化分析。

Adhesively bonded scarf repairs are the preferred method for repairing laminated composite structures,limited mainly by the amount of material removal associated with scarfing.In addition to the high strength restoration,scarf repairs also enable recovery of the original external surface as required by aerodynamic and/or external mould line considerations.In this investigation,an optimization method has been developed for determining the optimum scarf repair angles,adhesive thickness and scarf patch material for a given biaxial loading condition.The scarf angle,adhesive thickness and scarf patch material was considered by adaptive response surface method（ASRM）.The optimum and near-optimum scarf repair model are presented and discussed with respect to computational model using the finite element method.As a result,boron fiber scarf patch is the best with optimal matching modulus.When the scarf angle and adhesive thickness increased,the instability load also increased,then went into their matching zone,the instability load got its maximum value quickly.Once the value of scarf angle and adhesive thickness went out of their optimal matching zone,the instability load reduced soon.Meanwhile the matching between scarf repair patch material and the parent structure material is very important.It reveals that the ASRM method can realize the stability optimization of scarf repaired laminates with high efficiency.