Study On Interface Morphology Optimization And Bonding Properties Of Impact Bar Metallic Framework Surface By Laser Micro-molding

Impact bar is a kind of high elastic and high strength rubber/metal composite formed by metal substrate treatment and hot vulcanization molding technology,and widely used in aerospace,mining,automotive,heavy industrial machinery,power plants,grain and oil transportation,cement plants and other fields.While it is found in the practical engineering application that surface contamination and skeleton deformation after sandblasting seriously affect the surface quality and service life of impact bar.A new method is presented in this paper to improve the bonding properties by laser micro molding technology.The new approach explored the bonding mechanism and mechanical properties of rubber/metal composite,analyzed the laser energy conversion mechanism,laser beam generation mechanism and laser machining micro molding mechanism,designed the surface geometry of nested aluminum alloy framework,and studied the mechanism laser micro-molding process and the applicability of typical aluminum alloy geometry.The main contents of this thesis are as follows:(1)Investigated the bonding mechanism and mechanical properties of impact bar;summarized the mechanism of rubber/metal bonding and its application in practical industry;analyzed the main failure forms and causes of failure of rubber/metal;and provided a theoretical basis for the study of rubber/metal bonding process.(2)Studied the mechanism of laser energy conversion,laser beam generation and laser machining micro modeling;analyzed the geometric morphology of laser micro modeling of 4 typical industrial aluminum alloy skeleton materials by experiments;demonstrated the process consistency and mechanism of treating the metal skeleton surface of buffer strip by laser micro molding process;designed the surface geometry and the corresponding process parameters of the nested aluminum alloy framework at the same time.(3)Designed laser micro molding experiment,composite molding experiment and adhesive experiment;determined the main factors of the geometry and morphology of laser micro modeling;taken the maximum failure load and the minimum failure load as the experimental bonding performance index.The optimal solutions for the parameters of the laser micro molding technology are(1.5mm,0.01 mm,2)and(1.5mm,0.18 mm,2),respectively.It is proved that the laser micro moulding process can obtain a s Tab.bonding performance and a better bonding quality of the composite interface.(4)Evaluated and analyzed synthetically the metal surface bonding failure load,microstructure and forming mechanism of not treated,sand blasting and laser micro molding specimens by contrast experimental method;obtained the maximum failure load and the minimum damage load parameter pressure,the number of mesh and the optimum angle of the sand blasting group which are(0.7MPa,80#,60°)and(0.5MPa,80#,60°),respectively;found that the optimal failure load of sand blasting group is about 1 / 3 of the optimal failure load of laser group;utilized SEM and EDS analysis found the ideal R-C and R-type failure forms occurred in the laser group;proved the applicability of laser micro molding technology;provides theoretical guidance for the application of laser texturing in the field of rubber/metal bonding properties.