STRUCTURE MATCHING DESIGN OF LIGHTWEIGHT CFRP/METAL-LINED COMPOSITE HYDRAULIC CYLINDER

Hydraulic cylinder is the component with the largest proportion of the weight moving with the host equipment in the hydraulic system. Its lightweight design can help reduce the equipment's weight and improve the load, endurance and maneuvering performance, which has become the design development direction of hydraulic cylinder at present. Carbon Fiber Reinforced Polymer (CFRP), as a new lightweight material, has the advantages of higher specific stiffness/strength, lower thermal expansion coefficient, better corrosion resistance and fatigue resistance compared with aluminum alloy and high-strength steel materials. The composite manufacturing of hydraulic cylinder with CFRP and metal lining is the main technical means for the lightweight design of hydraulic cylinder at present. However, CFRP has the properties of material anisotropy on the macro level. How to make full use of this characteristic of CFRP and reasonably design the number and direction of fiber layering is the key problem to be solved in lightweight designing of the hydraulic cylinder. In this paper, a hydraulic cylinder served in an aviation actuator is lightweight designed by using the method of combining CFRP and aluminum alloy lining. According to the technology of finite element method, the effect of fiber layup sequence, direction, quantity and metal lining thickness on the performance of composite hydraulic cylinder is studied. The structure design method of the metal lining and the CFRP in the composite hydraulic cylinder are developed, and the effect of 55% weight reduction of the hydraulic cylinder is realized.