Computer Simulation of Wetting and Flowing Behaviors of Filler Metal during Laser Brazing Process

Abstract:

The wetting and flowing behaviors of the filler metal during laser brazing process were analyzed by the computer simulation. Two situations of the wetting and flowing during laser brazing were modelled, i.e., the metled Au-18%Ni and Ag-10%Pd filler metals on the butt joint of Inconel 600, and the melted Cu-8%Sn filler metal on the dissimilar butt joint of type 304 stainless steel to Cu. The filler metal droplet wetted and spread on the base metals and simultaneously infiltrated into the joint gap with the lapse of time. The Au-Ni and Ag-Pd filler metal infiltrated into the 0.3mm wide joint gap at the completion of brazing even in the single beam brazing. The Au-Ni filler metal did not infiltrate into the joint gap completely at the brazing clearances of 0.1-0.2mm in the single beam brazing, however, it could be filled up in the joint gap in the tandem beam brazing. The Cu-Sn filler metal wetted on the both base metals of stainless steel and Cu and filled up the 0.3mm wide joint gap when the location of preheating beam deviated in 0.5mm to Cu substrate, however, it did not infiltrate into the joint gap completely at the deviation distance of preheating beam to Cu substrate being 1.0mm. It followed that the wetting and flowing behaviors of the filler metal during laser brazing process could be predicted by the computer simulation.

• Periodical: Materials Science Forum (Volumes 580-582)
• Pages: 271-274
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.580-582.271
• Online since: June 2008
• Authors: Kazuyoshi Saida, Woo Hyun Song, Kazutoshi Nishimoto
• Keywords: Computer Simulation, Filler Metal, Laser Brazing, Metal Flow, Tandem Beam, Wettability

References

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DOI: 10.4028/www.scientific.net/msf.502.493

[2] K.Saida, W.Song and K.Nishimoto : "Laser Brazing of Alloy 600 with Precious Filler Metals", Sci. and Technol. of Welding and Joining, 11[5] (2006), pp.694-700.

DOI: 10.1179/174329306x148011

[3] K.Saida, W.Song and K.Nishimoto : "Diode Laser Brazing of Aluminum Alloy to Steels with Aluminum Filler Metals", Sci. and Technol. of Welding and Joining, 10[2] (2005), pp.227-235.

DOI: 10.1179/174329305x37060

[4] Flow Science, Inc. Customized by CFD Lab., (2006). Fig.7 Comparison of flow behavior of filler metal droplet between calculated and experimental results Experimental results Deviation distance of preheating beam (mm) 0.0095 0.0128 0.0102 Solidification time (s) Calculated results Cu Type 304 Cu Cu Cu Type 304 Cu Type 304 Type 304 Type 304 Impossible to braze 1mm 1.0 0.5 0 Fig.6 Flow of filler metal droplet on type 304 stainless steel to Cu dissimilar joint (Deviation distance : 0.5mm) Elapsed time : 0.012s Elapsed time : 0.0128s Elapsed time : 0.0075s Elapsed time : 0.007s Elapsed time : 0.0065s Elapsed time : 0s 1130K 1200K 1275K 1350K 1425K 1130K 1200K 1275K 1350K 1425K 1130K 1200K 1275K 1350K 1425K 1130K 1200K 1275K 1350K 1425K 1130K 1200K 1275K 1350K 1425K 1130K 1200K 1275K 1350K 1425K Deviation distance of preheating beam : 0.5mm Brazing clearance : 0.3mm Cu Type 304 Cu Type 304 Cu Type 304 Cu Type 304 Cu Type 304 Cu Type 304 Brazing clearance (mm) Base metal : Inconel 600, Filler metal : Au-18%Ni Single / main beam power : 300W Preheating beam power : 100W 0.10 .2 Single beam brazing Tandem beam brazing 500µm Fig.5 Comparison of flow behavior of filler metal droplet between single and tandem beam brazing with varying brazing clearance