Adjust dilution level to suppress the precipitated phase by dilution level model of dissimilar metal laser welding with filler wire. (May 2020)

• Record Type: Journal Article
• Authors: Cheng, Bo; Wu, Dongjiang; Liu, Jun; Cui, Qiang; Zhou, Siyu; Ma, Guangyi; Niu, Fangyong
• Is Part Of: Optics & laser technology. Volume 125(2020)
• Publication Date: 2020-05
• Subjects: Dilution level -- Laser welding -- Filler wire -- Dissimilar metal -- Nickel-based alloy -- Precipitated phase; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2019.106025
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: The relationship model between laser parameters and dilution level is obtained. The E and VF directly affect dilution level and have a linear relationship with it. Defocusing distance and pulse width affect dilution level of 304 by changing η m . Welding speed and laser beam offset affect dilution level of 304 by changing λ. A higher or lower dilution level can reduce volume fraction of precipitated phase. Abstract: To suppress the precipitated phase by adjusting the dilution level of 304 in the dissimilar metal (Hastelloy C-276/SUS 304) laser welding with filler wire, a mathematical model was established between laser parameters and the dilution level of 304 through energy conservation and mass conservation. And the model was verified by the corresponding experiment. The dilution level of 304 is linear with the single pulse energy E and inverse of wire feeding speed (1/ VF ), and it is also affected by energy melting efficiency and the ratio of two base metals melting. The dilution level of 304 is positively correlated with energy melting efficiency and negatively correlated with the ratio of two base metals melting. Defocusing distance and pulse width can affect dilution level of 304 by changing energy melting efficiency. Welding speed and laser beam offset can affect dilution level of 304 by changing the ratio of two base metals melting. At the same time, the influencing mechanism of the dilution level of 304 on the precipitated phase is revealed. The precipitated phase is directly related to the dilution level of 304. With the increase of dilution level of 304, the volume fraction of precipitated phase increases first and then decreases. When the dilution level of 304 is 24.0% ~ 35.2%, the volume fraction of precipitated phase is the biggest. And when the dilution level of 304 arrives to about 73.0%, the precipitated phase approximately disappears. As the result, the dilution level of 304 can be adjusted to suppress the precipitated phase by the dilution model in the laser welding Hastelloy C-276/SUS 304 with filler wire.