Research on strengthening aluminum alloy double-hole thin components based on pulsed electromagnetic force drive

As an innovative non-contact special strengthening process, electromagnetic cold expansion technology drives metal hole components to undergo plastic deformation and introduces residual compressive stress through pulsed electromagnetic force, which can significantly improve the fatigue life of hole components and effectively overcome problems such as surface damage and uneven stress distribution existing in traditional contact cold expansion technology. However, current research on this technology mainly focuses on the strengthening of single-hole components, while studies on the strengthening of multi-hole components in engineering structures remain very limited. For this reason, this paper takes 6063-T6 aluminum alloy double-hole components as the research object, focusing on exploring the process characteristics and performance advantages of electromagnetic cold expansion technology in the strengthening of double -hole components. Results from numerical simulations and experimental studies show that under a single pulse discharge, both holes in the double-hole component achieve uniform diameter expansion deformation from 6.00 mm to 6.10 mm, and a residual compressive stress field with a peak value of -230 MPa is formed around both holes. Fatigue performance tests indicate that after strengthening by electromagnetic cold expansion, the fatigue life of the double-hole components is increased by 2.34 times compared with initial samples. This not only verifies the applicability of electromagnetic cold expansion technology in the strengthening of multi-hole components but also provides important technical support for the application of electromagnetic cold expansion technology in anti-fatigue manufacturing of key aerospace components such as multi-hole connections of aircraft skins and engine mounting hole groups.