Effect of high magnetic field on the wetting behavior of molten Al-Cu alloy and Cu substrate

Reactive wetting systems between molten metal and solid metal have found broad applications in various fields, including brazing, soldering, composite material fabrication, etc. This study examines the wetting behavior and metallurgical reaction between molten Al-Cu alloy (liquid) and Cu (solid) during heating and holding processes without and with a high magnetic field (HMF). Our findings indicate that HMF decreases the contact angle during the heating process and the earlier holding stage. HMF weakens the formation of the intermetallic compounds during the earlier holding stage, but intensifies it during the later holding stage. At the later holding stage, the melt surface under the HMF exhibited a concave depression. However, the contact angles and internal microstructures under both conditions during the final holding stage show no significant difference. During the initial heating stage, Lorentz-force-induced suppression of convection facilitated the accumulation of liquid phase at the interface, thus initiating earlier wetting. As heating proceeds, intense thermo-electromagnetic convection at the solid–liquid interface promotes morphological evolution of the melt. In the later holding stage, the melt is subjected to a compressive effect due to the Lorentz force. Overall, this work clarifies how a high magnetic field can regulate interfacial diffusion, highlighting its promising potential for controlling reactive wetting in metallurgical systems.