With the electronic industry’s rapid development, the preparation of the functional surface of electronic devices has become a critical link in the high-precision electronic components’ application. The demand for 316L stainless steel with functional gold plating is increasing. Given the local functional requirements of electronic devices and the high-cost limitations of precious metal coatings, enterprises typically use the local electroplating approach for production. However, with the continuous enhancement of the performance of electronic devices, the product structure tends to be complex and puts forward higher requirements for the dimensional accuracy of the deposition area, as well as the design and manufacture of profiling fixtures are becoming more challenging, and the production efficiency and yield by this approach are declining, which poses a challenge to meet the production demand of high-end products. Thus, the development of new high-efficiency micro-electrochemical local gold deposition technology offers new ideas for developing domestic electronic devices, chip packaging, and other high-precision technologies, and is of certain importance for China’s industrial upgrading and meeting international demand for high-end products.

To solve the problems of difficult direct electrodeposition, complex pretreatment, and poor flexibility of existing local electrodeposition technology on 316L stainless steel substrate, the laser is presented into the electrodeposition system to eliminate the oxide film on the surface of stainless steel and induce maskless localized electrodeposition on the substrate surface. The machining mechanism and coating properties are investigated theoretically and experimentally using scanning electron microscopy (SEM), X-ray dispersion spectroscopy, cyclic voltammetry (CV), and current-time curve. The influence of laser single pulse energy, scanning speed, and pulse frequency on the surface morphology of the coating is explored, and the heat accumulation influence on the deposition accuracy is examined.

Laser scanning 316L stainless steel surface can efficiently eliminate the surface oxide film, activate the substrate, and realize the simultaneous elimination of oxide film and electrodeposition, without disrupting the plated area (Fig. 3). The limited increase of laser single pulse energy aids to enhance the coating surface morphology and reduces the coating roughness. However, when the single pulse energy is increased further, the bare substrate, pores, and other defects on the coating surface increase, and the surface quality decreases (Fig. 6). By gradually increasing the laser scanning speed, the flatness of the coating is effectively enhanced, and the best state is realized when the scanning speed is 10 mm/s. When the scanning speed is improved further, the coverage and density of the coating are considerably increased, and the particles are coarsened (Fig. 10). The increase of laser pulse frequency improves the laser thermal effect’s accumulation, effectively improves the electron transfer rate, speeds up the nucleation rate in the electrodeposition process, and refines the grains (Fig. 11). The prolonged accumulation of the laser thermal effect will lead to stray deposition in the laser’s unscanned area, reduce the dimensional accuracy of the coating, as well as cause low adhesion and density of the stray deposition layer, and uneven element distribution (Fig. 12). The optimal laser parameters are generated through the optimization test. The gold coating prepared under the optimal laser parameters has good service properties like adhesion and corrosion resistance, and the typical local gold coating pattern has high precision and beauty (Fig. 18).

We propose a laser induced localized electrodeposition process on a stainless steel surface. This process integrates the elimination of oxide film on the stainless steel surface and the electrodeposition phase to realize high-efficiency localized electrodeposition on the 316L stainless steel surface. First, we examine the test mechanism and then obtain the influence of different laser parameters on the gold coating through a series of single-factor tests. Finally, we get the optimal parameters of laser induced electrodeposition of gold coating: the laser scanning speed, laser pulse frequency, laser single pulse energy, number of laser scannings are 10 mm/s, 3000 kHz, 5 μJ, and 2, respectively. We assess the service performance of the coating prepared under the optimized parameters by bending test, thermal shock test, and corrosion test. Through observation, it is discovered that the service performance of the coating is good and can meet the application requirements. This process is predicted to be used in the high-precision electronic component industry and offers new ideas for the surface treatment and packaging of electronic components.