Buttwelding of Mg-Cu-Gd Bulk Metallic Glass using a High-brightness Fiber Laser

Autor: Terajima, Takeshi, Kimura, Hisamichi, Inoue, Akihisa
Jazyk: angličtina
Rok vydání: 2010
Předmět:
Zdroj: Transactions of JWRI. 39(1):61-64
ISSN: 0387-4508
Popis: The light metal based metallic glass Mg₆₅Cu₅₅Gd₁₀ has low specific gravity and excellent mechanical properties and thus is expected to be a useful structural material. However, welding of Mg₆₅Cu₂₅Gd₁₀ is difficult since it immediately crystallizes if the quench rate is lower than the critical value. In this study, a high-brightness fiber laser with an ultrahigh power density of several megawatts per square millimeter, which corresponds to the power density of an electron beam and is a well suited for this purpose, is examined for welding Mg₆₅Cu₅₅Gd₁₀. The laser beam was transmitted through an optical fiber and focused on the butt surface of the Mg₆₅Cu₂₅Gd₁₀ rods that were synchronously rotated at 3000 rpm at 0.5 MPa. The molten alloy that forms following laser irradiation was extruded from the joint, and the specimens were successfully welded. The microstructure observed by micro-focus X-ray diffraction showed that the crystalline phase was not present inside the joint but was in the extruded region. The success of the proposed welding is likely attributable to the pressure applied to the specimens, which plays an important role in extruding the crystalline phase from the joint.
Databáze: OpenAIRE