Experimental Study On The Bonding Repair And Mechanical Properties Of Composite Laminates

As the composite material is widely used in the field of civil and military,the structure will appear all sorts of damage in the process of service.For some influence the damage of subsequent use,direct replacement components do not conform to the requirements of the economy,it is very necessary to repair.Having mechanical connection repair methods and glue to repair,but mechanical connection repair because of its need to be in the original injury drilling and easy to produce stress concentration instead of the original component unnecessary damage,so now the gluejoint repair more and more application in engineering practice.In order to obtain better repair effect,in the process of bonding repair,this paper analyzes the factors which influence the effect of repair is the main research contents in this paper.In this paper,the main research work is as follows:1.With SK chemicals(Qingdao)co.,LTD TR50 carbon fiber presoak materials as raw materials,carbon fiber density of 1.77g/cm3,resin density of 1.2 g/cm3.Laying the layers of composite laminated plates is 16 layers,each layer thickness is 0.0125 mm,through the thermal curing is 2 mm thick laminated plates.In bonding process of adhesive joint strength analysis,the stress concentration of the smallest cant lap,and chose has a high shear and peel strength Araldite@2015 ductile adhesive bonding to repair.Ultrasonic C scan system is ultrasonic testing and control of microcomputer,data acquisition,storage,processing,and image display system together.The scanning system of the computer control ultrasonic probe(transducer)alternating scan on the work piece,will scan point some parameters with different color display.For polishing after cementing ultrasound scans of composite laminated plate,a varying cross-section direction of scanning images,by observing the color of the glue it determine the Araldite@2015 ductile adhesive can well ensure the thickness of the rubber and cementing quality.2.To the laminated plates of different layer Angle after cant glue joint repair effect is good or bad,cross-ply laminated cylindrical shell is adopted two typical[±45°]4s and[0°/90°]4s,the glue joint specimens for mechanical properties test after repair,the specimen[±45°]4s after repair maximum bending recovery efficiency can reach 119.6%,maximum tensile recovery efficiency can reach 71.4%;the[0°/90°]4s layer of maximum bending specimen after repair recovery efficiency can reach 82.1%,maximum tensile recovery efficiency can reach 70.6%.3.For different laminated plates in the tilt of the repair after cant glue joint repair of good or bad,the effect of the two kinds of typical layer of laminated plates are selecting the four different and a greater degree of differentiation of repairing slope 1:10,1:15,1:20,1:25.To[±45 °]4s layer of the specimen after bending and tensile experiment data is analyzed,when the slope is 1:20,bending and tensile properties can meet the demand of repair;[0°/90°]4s layer of the specimen after bending and tensile experiment data is analyzed,when the slope is 1:25,bending and tensile properties can meet the demand of repair.4.Using the finite element analysis software ABAQUS,the bending and tensile experiments under the conditions of specimen is analyzed,the laminated plates and rubber stress distribution nephogram,has a good fit with the experimental results.