Research On Pressure Retaining And Cushioning Characteristics For Bonding Of Brittle Structural Parts

At present,the bonding process of aircraft is mainly applied to the connection between composite materials.In the pressure holding stage of the bonding process,direct rigid compression on curved resin based brittle composites,which is high in strength,light and fragile,will cause the stress concentration on the outer surface of the brittle composite.Therefore,it is necessary to buffer the compression process to realize the flexible pressure protection of the brittle structural parts,otherwise the safety requirements can not be met.However,for the moment,there are the following problems regarding the characteristics of the pressure-buffered cushioning member.Firstly,suitable cushioning material has not been found.Secondly,the optimization scheme of buffer uniformity is lacked.Thirdly,the necessary executive force algorithm is also lacked and the the side slip in the pressure holding process of the fragile structure is serious.In view of the above problems,this paper sets up a hardware experimental platform and uses Abaqus simulation and experimental analysis to do the research.The main contents of this paper are as follows:(1)The performance and application scope of the commonly used cushioning materials are studied.Starting from the safety and reliability of the cushioning buffer,Shore 00 40 degree silicone rubber was selected as the material of pressure retaining and cushioning for brittle structural parts.(2)Six commonly used constitutive models of Hyperelastic Materials are expounded.The constitutive model parameters of the selected materials are fitted,which provides data basis for finite element analysis,through uniaxial compression and volume compression test.(3)The evaluation model of the buffer uniformity of the fragile structure and the optimization plan of the buffer uniformity are put forward,including its optimization performance and application scope.The reliability of the optimization scheme is proved by the simulation and experimental verification methods.(4)Aiming at the sideslip phenomenon in the bonding process of brittle structures,the equivalent point and equal force algorithm are put forward.Combined with finite element simulation and case studies,it is verified that the lateral displacement of brittle structure is controlled in 0.1mm by the algorithm in the process for packing.