Fabrication of Aluminum Foam-Filled Thin-Wall Steel Tube by Friction Welding and Its Compression Properties

Abstract

Aluminum foam has received considerable attention in various fields and is expected to be used as an engineering material owing to its high energy absorption properties and light weight. To improve the mechanical properties of aluminum foam, combining it with dense tubes, such as aluminum foam-filled tubes, was considered necessary. In this study, an aluminum foam-filled steel tube, which consisted of ADC12 aluminum foam and a thin-wall steel tube, was successfully fabricated by friction welding. It was shown that a diffusion bonding layer with a thickness of approximately 10 μm was formed, indicating that strong bonding between the aluminum foam and the steel tube was realized. By the X-ray computed tomography observation of pore structures, the fabrication of an aluminum foam-filled tube with almost uniform pore structures over the entire specimen was confirmed. In addition, it was confirmed that the aluminum foam-filled steel tube exhibited mechanical properties superior to those of the ADC12 aluminum foam and steel tube. This is considered to be attributed to the combination of the aluminum foam and steel tube, which particularly prevents the brittle fracture and collapse of the ADC12 foam by the steel tube, along with the strong metal bonding between the aluminum foam and the steel tube.

Aluminum Foam-Filled Steel Tube Fabricated from Aluminum Burrs of Die-Castings by Friction Stir Back Extrusion

“…TiH 2 powder (<45 µm) was used as the blowing agent. The amount of TiH 2 was one mass% relative to the mass of ADC12 burrs in accordance with reference [13]. As shown in Figure 2b, the mixture was placed in a SUS304 stainless-steel tube fixed by a steel jig.…”

“…Friction stir back extrusion (FSBE) has been developed for coating wear-resistant Al-25%Si on the surface of an Al-Si-Cu alloy AC2B engine cylinder [10], and for fabricating Al tubes and copper tubes with a fine grain structure from bulk starting materials [11,12]. Hangai et al developed a fabrication process for Al foam-filled steel tubes [13,14] and Al foam-filled Al tubes [15,16] by FSBE. In this process, a bulk Al precursor was placed into a metal tube; then a rotating tool was plunged onto the precursor.…”

In situ manufacturing and mechanical properties of syntactic foam filled tubes

“…All previous studies have indicated that the interaction between the foam and the tube improves the deformation behaviour of the structure and results in a high energy absorption of FFTs both under quasi-static [7,[10][11][12][13][14] and dynamic loading conditions [15,16]. However, Sirinath et al observed that an aluminium foam filled steel tube has a lower specific energy absorption when compared to an empty tube [7].…”

Foaming of friction stir processed Al/MgCO3 precursor via flame heating

“…FSP is also successful in the manufacture of foam filled tubes. Investigation of Al foam/Al tube [19], Al foam/steel [20] tube has demonstrated a strong bond of the precursor to the interior of the tube. Although, foaming of precursors as a result of frictional heating has been proved to be a viable option [21], the extraction of the foam, however, can be a problem.…”