Process Control Features of Electron-Beam Additive Manufacturing of Austenitic Stainless Steel

Abstract Currently, casting, pressing and other conventional methods are used to create metal parts of complex shape. The disadvantages of such methods are the complexity and multi-stage peculiarity of the process, high-energy consumption, and poor efficiency. This work considers the technology of wire-feed electron-beam additive manufacture, allowing increasing productivity at the expense of decreasing the amount of mechanical treatment and consumable raw materials. Despite the number of advantages, there are still questions, related to the study of the influence of technological parameters of electron-beam additive manufacture on the structure and properties of articles. Therefore, the influence of technological parameters on the stability of the process of layerwise application and formation of the articles from the AISI 304 wire by the method of electron-beam additive manufacture has been studied in the work. The electron beam current, the linear print speed and the layer fill factor at a constant accelerating voltage were used as variable parameters. It has been established that on the whole it is possible to form the article without defects and without surface melting of the previously formed layers with the ultimate tensile strength of 583 MPa with the layer fill factor equal to 1.3, current of 40 А, and a linear velocity of 180 mm/min. The use of modes with a linear velocity of 320 mm/min and the layer fill factor of 1.3, when the current varies, does not allow forming a sample as a whole. It has been shown that when the process parameters of electron-beam additive manufacture vary, providing formation of the article as a whole, it is possible to obtain articles with the ultimate tensile strength of 558-595 MPa.