PULTRUSION PROCESSING OF CONTINUOUS THERMOSET PROFILES WITH LOCALIZED VARIABLE CROSS-SECTION

THE PULTRUSION PROCESS IS A CONTINUOUS METHOD FOR THE MANUFACTURE OF COMPOSITE PROFILES EMPLOYING EITHER THERMOSET OR THERMOPLASTIC POLYMER MATRICES. PULTRUDED PRODUCTS ARE NOTED FOR HIGH-FIBER VOLUME CONTENTS RELATIVE TO PRODUCTS MADE BY ALTERNATIVE COMPOSITE PROCESSES MAKING THEM MATERIALS OF CHOICE IN MANY STRUCTURAL APPLICATIONS. THE WELL-ESTABLISHED THERMOSET TECHNOLOGY, WHICH REPRESENTS NEARLY THE ENTIRE CURRENT COMMERCIAL MARKET, IS LIMITED TO PRODUCT GEOMETRIES OF CONSTANT CROSS-SECTION RELATIVE TO THE LINEAR MACHINE DIRECTION WITH NO OPPORTUNITY FOR SUBSEQUENT REFORMING. THERMOPLASTIC PULTRUSION TECHNOLOGY, WHILE IN ITS INFANCY, DOES ALLOW FOR LIMITED GEOMETRY REFORMING AFTER PRIMARY MOLDING; HOWEVER, THE COST OF RAW MATERIAL AND PROCESSING STEPS IS SEVERELY COST-PROHIBITIVE FOR MOST APPLICATIONS. SUCH REFORMING CAPABILITY IS DESIRABLE IN ORDER TO INTRODUCE FLANGES, OFFSETS, AND BOSSES, FOR EXAMPLE, WHICH CAN PROVIDE SECONDARY STRUCTURE FOR LOAD TRANSFER AND IMPROVED JOINT EFFICIENCY. THIS RESEARCH PROJECT INVESTIGATES THE FEASIBILITY OF A THERMOSET PULTRUSION PROCESS MODIFICATION WHICH ALLOWS FOR CONTINUOUS PRODUCTION WITH INTRODUCTION OF VARIABLE CROSS-SECTION AT PROGRAMMED LOCATIONS. THE FEASIBILITY OF THIS PROCESS WILL BE ESTABLISHED THROUGH PROCESS MODELING EMPLOYING FINITE ELEMENT ANALYSIS TECHNIQUES AND VERIFIED THROUGH PROCESS SIMULATION AND PROTOTYPE TRIALS.