Consistent layer height in plasma metal deposition by adjusting wire feed

Abstract

The production of large, near-net-shape components using additive manufacturing with plasma metal deposition (PMD) is gaining increasing importance. In this process, the arc plasma melts the wire material locally and builds up the geometry layer by layer through deposited metal droplets. Despite the advantages, such as flexibility in geometry design and Efficient material usage, achieving "First Time Right" production remains a challenge. Uncontrollable dynamic effects in the process often lead to deviations in layer height, which can even result in process termination. This paper presents a process application to compensate for these deviations by automatically adjusting the wire feed. Continuous monitoring of the arc voltage signal during the PMD process enables real-time detection of layer height variations. An automated data acquisition system is used to identify the process behavior to design the control algorithm. Experimental results demonstrate that the proposed layer height control significantly enhances process stability, advancing the PMD technology closer to achieving "First Time Right" additive manufacturing.