Development of Fiber Laser Weld Parameters for Stainless Steel and Refractory Metals

Elmer, J ; Pong, R

关键词: APPROXIMATIONS;    COLLIMATORS;    CONFIGURATION;    FIBERS;    FOCUSING;    LASERS;    NITROGEN;    OXYGEN;    PENETRATION DEPTH;    REFRACTORY METALS;    SHIELDS;    STAINLESS STEELS;    TANTALUM;    TARGETS;    VANADIUM;    WELDING;   

DOI  :  10.2172/956844
RP-ID  :  LLNL-TR-413222
PID  :  OSTI ID: 956844
Others  :  TRN: US1005008

学科分类：材料科学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

Laser welds were made in 21-6-9 stainless steel, vanadium and tantalum using LLNL's new 6kW fiber laser to target 1 mm penetration depths. The materials were machined into flat coupon samples with standard step-joint geometries, and were welded in a continuous wave mode. The laser was characterized using the Primes laser beam diagnostic system so that the beams can be reproduced in the future. The optical configuration consisted of a 200 {micro}m fiber, 200 mm collimator and 250 mm focusing lens, which delivered electron-beam level power densities in the 5 to 20 kW/mm2 range. The three different materials required different power densities to produce the desired penetration, and this report summarizes the results of this screening study that was directed at developing a first approximation to the proper welding parameters for future work. The results show that 1 mm penetrations can be achieved using a 400W beam for 21-6-9 stainless steel, a 600W beam for vanadium, and a 1,100W beam for tantalum using sharp focus and a travel speed of 40 inch/min. Future welds should incorporate a trailing gas shield to prevent discoloration of the surface and to prevent oxygen and nitrogen pickup in the welds.