Research on Accurate Control of Gas Temperature in Cold Spraying Based on PID Control Strategy

Gas temperature is one of the critical parameters that affects the velocity, temperature of particle and the consequent coating quality in cold spray additive manufacturing. The accurate control of the gas temperature is of great importance to the stability of the gas heating efficiency, deposition efficiency, and microstructure of coatings. Therefore, a numerical model was established using ANSYS-FLUENT to study the influence of PID strategy and traditional switch control strategy on the precise temperature of cold spraying gas. Results showed that both the stable time and the overshoot of gas temperature were significantly optimized when the PID strategy was applied. Moreover, the influences of the three factors (proportional, integral and derivative) in PID strategy on the stable time and the overshoot of gas temperature were investigated using an orthogonal experiment. The experimental results showed that the stable time and the overshoot were mainly affected by the proportional parameter and the integral parameter, respectively. With the increase of the proportional parameter and the integral parameter, the stable time and the overshoot rate reduced, and the control accuracy of the gas temperature increased.