ВПЛИВ КІЛЬЦЕВИХ КАНАВОК ХОЛОДНОГО ОБТИСКУ НА ДОВГОВІЧНІСТЬ ПАНЕЛЕЙ КРИЛА З ФУНКЦІОНАЛЬНИМИ ОТВОРАМИ

This article studies in detail the method of cold extrusion annular grooves to solve the problem of aircraft fatigue life extension that reduces the fatigue life of aircraft wing panels due to functional holes. This method is a very simple and effective anti-fatigue manufacturing technology. In order to simulate the different wing panels with functional holes, the experiment is designed to extrude the specimen with different extrusion forces to obtain annular grooves of different depths. Fatigue tests are conducted on specimens with annular grooves. The test results show that: 1) Cold extrusion annular grooves can extend the fatigue life of wing panels with functional holes; 2) The fatigue life of wing panels with functional holes is affected by the depth of the cold extrusion annular groove. The fatigue life changes in an inverted "V" shape as the depth of the cold extrusion annular groove increases; 3) When cold extrusion annular groove depth is 0.26mm, the fatigue life of specimen with holes is maximum, and the fatigue life is increased by 2.35~32.9 times when specimen thickness is 5 mm