Research On Hot Pressing Equipment Of Advanced Pultrusion Manufactured Hat-stiffeners And Mechanical Properties

Composite materials such as girders, beams etc. that form stiffened panel structured by co-curing，co-bonding and secondary bonding with panels are widely used in aeronautic and astronautic area dueto their light-weight and high-strength. The traditional mould process involves hand lay-up process,autoclave process etc, which are inefficient and costly. Thus, modifying the manufacturing technicwithout compromising the structural quality and reducing the manufacture cost has become one of thehotspots in current research.Advanced Pultrusion (ADP) is a recently developed composite-material crafting technic. Though ithas already had mature applications in other countries, it is still in the exploratory stage in China. Thispaper studies the equipment and process of ADP using the common hat-stiffeners as test subject. Themain work contains the following:（1）After theoretical analysis, through sectional size adjustment of the products, the dipetalous hotprocessing mold can achieve the direction coincidence of pressure and compression displacement, andthen the goal values of the hat-stiffeners are proposed. With the given sectional size of hat-stiffeners, thehot pressing device and the pull-out device are theoretically analyzed and designed. The prototype ofhot pressing equipment is developed by designing the pressuring scheme and the heating scheme.Furthermore, pultrusion equipment is developed by calculating the resistance that needs to be overcomeduring pultrusion.（2）Assemble the ADP system using the self-designed hot processing equipment, pultrusionequipment and feeding prepreg equipment. The pressure controlling system is completed by the ladderdiagram based on PLC. The heating controlling system is completed based on PID temperaturecontroller. Each component of the system is adjusted in order to make the whole system run inautomation. After trial hat-stiffeners are manufactured by the assembled ADP, their flaws are detectedand analyzed. Then proper solutions are put forth to improve the product to meet the previouslyproposed goal values.（3）The feasibility of the ADP made in this work along with the crafting technic is examined. Inaddition, the relevant mechanical parameters for hat stiffeners is measured through comparisonexperiments such as pull-off tests, flexural tests, interlaminar shear strength tests and compression tests,which lay foundations for future research. Finally, the impact of each crafting parameters has on themechanical properties of the parts is also discussed.