Vacuum brazing 5005 aluminum alloy to 1Cr18Ni9Ti stainless steel

Vacuum brazing of 5005 aluminum alloy and 1Cr18Ni9Ti stainless steel was carried out with Al-Si-Mg filler foil. The interfacial microstructure and mechanical properties of the brazed joints were investigated by scanning electron microscope, energy dispersion spectrometer, x-ray diffractometer and tensile test, respectively. The experimental result showed that the typical interface structure of the joints was 1Cr18Ni9Ti stainless steel/FeAl/FeAl₃/Fe_mAl_n+αAl/5005 aluminum alloy. With brazing temperature and holding time, inereased the shear strength of the joints increased firstly and then decreased. Besides, mechanical property tests showed thatwhen the brazing temperature was 580℃ and the holding time was15 min, the maximum shear strength of joints was 49 MPa. Moreover, the fracture form of the joints was mainly affected by the brazing temperature. When the brazing temperature was low, the joints fractured in the oxide layer and Fe_mAl_n+αAl layer. When the temperature was high, the joints fractured in Fe_mAl_n+αAl layer completely.