Product Code: PIC2008_P230

Laser Cladding of Az91D Magnesium Alloy with Ni-Si-Mg
Authors:
Ding Fan, Lanzhou University of Technology; Lanzhou Peoples Republic of China
Jianbin Zhang, Lanzhou University of Technology; Lanzhou Peoples Republic of China
Yufeng Zheng, Lanzhou University of Technology; Lanzhou Peoples Republic of China
Qiang Li, Lanzhou University of Technology; Lanzhou Peoples Republic of China
Presented at PICALO 2008

AZ91D Magnesium alloy was laser cladded with Ni-Si-Mg to enhance the surface hardness. The microstructures and phases of the cladded zone were characterized by optical microscope (OM), scanning electron microscope (SEM), and X-ray diffractometer (XRD). The micro-hardness could be improved up to a maximum of 500-550 Hv in Ni64.82Mg9.41Si25.77 (at.%) and 650-700 Hv in Ni70.83Mg6.27Si22.9 (at.%) as compared to 80 Hv of the as-received substrate. The high micro-hardness of the Ni-Si-Mg coating is due to a microstructure consisting mainly of Ni3Si, Ni31Si12 and Ni16Mg6Si7. With the increase of Mg content from 6.27 to 9.41, the diffraction peak intensities of Ni16Mg6Si7 and Ni31Si12 increased, while the diffraction intensity of Ni3Si decreased.