Closed-Loop Process Control for Electron Beam Direct Manufacturing

This project proposes the use of non-imaging optical measurement to discern the weld pool oscillations occurring during electron beam deposition, and thereby to infer the weld pool size. By knowing this weld pool size, it is possible to control the e-beam deposition process by suitably regulating heat input, wire feed rate, etc to ensure a consistent depth of penetration. This approach has the advantage of being simple, based on only one sensor, and capable of rapid real-time response. Phase I will investigate the ability of the proposed sensing approach to see weld pool oscillations during e-beam deposition and to distinguish between the signatures of nominal and off-nominal conditions. Phase II will then develop a control scheme based on these in-process measurements. The project team has considerable experience monitoring and controlling arc welding processes using similar approaches and will work with both end udders as well as e-beam machine experts to successfully implement the approach proposed herein. BENEFIT: successful execution of this work will result in a commercially viable system for monitoring and control of electron beam depositon processes, which will benefot a wide range of commercial and defense aerospace applicatoins initially, as well as other discrete parts manufacture.