Study on the soft magnetic properties, corrosion, and wear resistance of Ni-Co-W coatings deposited via laser-assisted electrochemical technique: Potential applications in advanced electromagnetic devices

Ni-Co-W alloy possesses several advantages, including exceptional hardness, outstanding wear resistance, and remarkable high-temperature resistance. The coating exhibits favorable soft magnetic performance when the Co content is high. This study combines the introduction of Co element and laser irradiation to explore the changing mechanisms in the soft magnetic properties, corrosion resistance, and wear resistance. Coatings are electrochemically deposited on copper substrates employing a pulsed current, and a Ni-Co-W coating is assisteddeposited utilizing a picosecond laser with a single pulse energy of 10 mu J. The experimental results reveal that when 12 g/L of CoSO4 center dot 7 H2O is added to the electrolyte, the Co elements significantly improve the soft magnetic properties of the Ni-Co-W alloy. Meanwhile, the reduction of WO42- is also promoted and the W content is increased (nearly 2.6 times, 1.95 Wt%), thereby obtaining microhardness, corrosion resistance, and wear resistance superior to Ni-W. Laser irradiation effectively increases the W content (nearly 2.3 times, 4.52 Wt%) while reducing surface defect. The increased W content alters the internal crystal structure and refines the grain. Moreover, laser irradiation significantly improves the soft magnetic properties (a 33.17 % increase in Ms, a 12.97 % increase in Hc, and a 5.66 % increase in Mr). This study achieves soft magnetic coatings with excellent corrosion and wear resistance through a laser electrochemical deposition process. It provides new processing ideas and methods for preparing soft magnetic alloy coatings and has broad application prospects in magnetic thin film storage devices and high-frequency electromagnetic devices.