Hangai Yoshihiko, Nakano Yukiko, Koyama Shinji, Kuwazuru Osamu, Kitahara Soichiro, Yoshikawa Nobuhiro
Graduate School of Science and Technology, Gunma University, Kiryuu 376-8515, Japan.
Graduate School of Engineering, University of Fukui, Fukui 910-8507, Japan.
Materials (Basel). 2015 Oct 23;8(10):7180-7190. doi: 10.3390/ma8105373.
Aluminum foam is usually used as the core of composite materials by combining it with dense materials, such as in Al foam core sandwich panels and Al-foam-filled tubes, owing to its low tensile and bending strengths. In this study, all-Al foam-filled tubes consisting of ADC12 Al-Si-Cu die-cast aluminum alloy foam and a dense A1050 commercially pure Al tube with metal bonding were fabricated by friction welding. First, it was found that the ADC12 precursor was firmly bonded throughout the inner wall of the A1050 tube without a gap between the precursor and the tube by friction welding. No deformation of the tube or foaming of the precursor was observed during the friction welding. Next, it was shown that by heat treatment of an ADC12-precursor-bonded A1050 tube, gases generated by the decomposition of the blowing agent expand the softened ADC12 to produce the ADC12 foam interior of the dense A1050 tube. A holding time during the foaming process of approximately = 8.5 min with a holding temperature of 948 K was found to be suitable for obtaining a sound ADC12-foam-filled A1050 tube with sufficient foaming, almost uniform pore structures over the entire specimen, and no deformation or reduction in the thickness of the tube.
泡沫铝由于其低拉伸强度和弯曲强度，通常通过与致密材料结合，用作复合材料的芯材，如在泡沫铝芯夹芯板和泡沫铝填充管中。在本研究中，通过摩擦焊接制造了由ADC12铝硅铜压铸铝合金泡沫和具有金属结合的致密A1050工业纯铝管组成的全泡沫铝填充管。首先，发现通过摩擦焊接，ADC12前驱体牢固地粘结在A1050管的整个内壁上，前驱体与管之间没有间隙。在摩擦焊接过程中未观察到管的变形或前驱体的发泡。接下来，结果表明，通过对粘结有ADC12前驱体的A1050管进行热处理，发泡剂分解产生的气体使软化的ADC12膨胀，从而在致密的A1050管内部产生ADC12泡沫。发现发泡过程中的保温时间约为 = 8.5分钟，保温温度为948 K，适合获得具有充分发泡、整个试样上几乎均匀的孔结构、且管无变形或厚度减小的良好的泡沫铝填充A1050管。
