Wire and arc additive manufacturing method for titanium alloy

A wire and arc additive manufacturing (WAAM) method for a titanium alloy, the method comprising the steps:

• (a) drawing a part model through three-dimensional (3D) drawing software;
• performing layered slicing on the part model through slicing software to acquire layered slice data;
• simulating the layered slice data through simulation software to generate a robot control code;
• importing the robot control code into a welding robot;
• performing, by the welding robot, a WAAM process with a titanium alloy on a pre-prepared base plate to form a multi-layer deposited metal including a total of 2 to 4 layers;
• applying, during the forming process, cooling and rolling to a side wall of the multi-layer deposited metal through a cooling and rolling device, wherein during cooling and rolling, 10-40° C. cooling water flows at a rate of 1,000-3,000 L/h, and a rolling stress on the multi-layer deposited metal is 50-400 MPa;
• (b) milling side and top surfaces of the multi-layer deposited metal;
• (c) performing, by friction stir processing (FSP) equipment, an FSP process on the multi-layer deposited metal after milling, and applying cooling and rolling to the side wall of the multi-layer deposited metal through the cooling and rolling device during the FSP process, wherein during cooling and rolling, 10-40° C. cooling water flows at a rate of 1,000-3,000 L/h, and a rolling stress on the multi-layer deposited metal is 100-800 MPa;
• (d) finish-milling the top surface of the multi-layer deposited metal to make the treatment surface smooth for a WAAM process in the next step;
• and
• (e) repeating the above steps cyclically until the multi-layer deposited metal is formed into an additive part with a preset shape and size,
• wherein the cooling and rolling device comprises a roller, a heat conducting cylinder and a heat conducting outer ring;
• the heat conducting outer ring is rotatably assembled on an outer wall of the heat conducting cylinder;
• the heat conducting cylinder is provided with an inner cavity;
• an upper surface of the heat conducting cylinder is provided with a cooling water inlet communicating with the inner cavity;
• a lower surface of the heat conducting cylinder is provided with a cooling water outlet communicating with the inner cavity;
• the roller is vertically fixed and assembled at a center of the upper surface of the heat conducting cylinder, and the roller moves synchronously with a welding gun of the welding robot and a stirring tool of the FSP device.