Analysis of Residual Stress and Fatigue Performance of Al-Li Alloy Riveted Panel

Abstract:

Automatic riveting is an important assembly technology in the aviation manufacturing industry. The distribution of residual stress around the rivet hole after the riveting process is closely related to the fatigue performance of the riveting structure. In this paper, ABAQUS software was used to establish the finite element model of the press riveting process of the 2060-T8 Al-Li alloy plate. It was found that the residual stress on the wall of the rivet hole after the riveting process gradually decreased from the place close to the rivet head to the place close to the rivet head. With the pressure riveting force increasing from 28.5kN to 46kN, the average residual stress of the hole wall of the riveted plate with the rivet material of 2117-T4 increases by 33%, and the uniformity of the residual stress distribution along the thickness of the wall plate increases by 180%. The average residual stress of the hole wall of the riveted plate with 7050-T73 rivet material is increased by 58%, and the uniformity of the residual stress distribution along the thickness of the wall plate is increased by 184%. The fatigue crack originated near the hole wall of the riveted lower plate. With the increase of the riveting force from 32.5kN to 42kN, the fatigue life of the riveted plate with the rivet material of 2117-T4 increased by 31%~80%, and the fatigue life of the riveted plate with the rivet material of 7050-T73 increased by 6%~161%. Compared with the riveted plate with rivet material of 7050-T73, the fatigue life of the riveted plate with rivet material of 2117-T4 under the same process conditions is increased by 12%~44%.

Key words:automatic riveting, finite element analysis;residual stress; fatigue performance