Pretreatment of CFRP by Amino Thermoset Abrasive Air Jet Machining

Abstract An effective pretreatment method of carbon fiber reinforced plastic (CFRP) aircraft skin was proposed. In this article, the function of the amino thermosetting abrasives entrained by the airflow on the CFRP aircraft skin is introduced and discussed to achieve the purpose of enhancing the coating adhesion and prolonging the service life. An orthogonal experiment with five factors and four levels was designed and carried out, including jet pressure, target distance and impact angle, moving speed and particle size. The best pretreatment process was obtained by analyzing surface morphology, wettability and adhesion. The erosion mechanism of CFRP coating pretreatment with abrasive impact was studied emphatically. The results show that the critical pressure for fiber damage is 0.4 MPa, and the better surface energy is 38.0 mN/m. Semi-ductile erosion has been identified as the main erosion mechanism of amino thermosetting abrasives eroding CFRP. Effective assurance was provided for the improved surface of the aircraft CFRP skin and enhanced coating adhesion in this study.