Effect of Ti content on the cell structure and compressive and energy absorption properties of Al3Ti/Al6061 foam composite

Abstract

Aluminium alloy foams are often used as cushioning parts for automobiles because of their excellent energy absorption properties and lightweight characteristics. Their energy absorption properties mainly depend on the cell structure of the foam, but the cell structure of aluminium alloy foams prepared by the powder metallurgy method is usually difficult to control. In this work, Al3Ti/Al6061 foam composite (AT-FC) was prepared by powder metallurgy using TiH2 as the blowing agent and a mixture of Al6061 and Ti powder as the foaming matrix. The effects of different Ti contents on the cell structure, cell distribution and morphology of AT-FC were focused on, and their mechanical properties under quasi-static compressive loading were investigated. The experimental results showed that different Ti contents could regulate the cell size and improve the cell morphology and distribution, in which AT-FC contains 7.5 wt% Ti had the best cell structure with an average cell size of about 1.56 mm and an average circularity of 0.82. By comparing the compressive yield strength, energy absorption and specific energy absorption of AT-FC with different Ti contents, the AT-FC with 10 wt% Ti had the best compressive yield strength of 8.96 MPa and AT-FC with 7.5 wt% Ti had the best energy absorption of 6.50MJ/m3.