Trajectory Generation and Coupled Numerical Simulation for Thermal Spraying Applications on Complex Geometries

Abstract

For high process reproducibility and optimized coating quality in thermal spray applications on complex geometries, atmospheric plasma spraying and high-velocity oxygen fuel torches are guided by advanced robot systems. The trajectory of the torch, the spray angle, and the relative speed between torch and component are crucial factors which affect the coating microstructure, properties, and, especially, the residual stress distribution. Thus, the requirement of high-performance thermally sprayed coatings with narrow dimensional tolerances leads to challenges in the field of robot-assisted handling, and software tools for efficient trajectory generation and robot programming are demanded. By appropriate data exchange, the automatically generated torch trajectory and speed profile can be integrated in finite element method models to analyze their influence on the heat and mass transfer during deposition. Coating experiments assisted by online diagnostics were performed to validate the developed software tools.

Automatic Robot Trajectory for Thermal‐Sprayed Complex Surfaces

“…e demand for coating on curved surface has increased over the last few years. It requires hundreds of points in the trajectory and different orientation for each point, so it is very difficult to create such a trajectory by manual point-by-point programming method [7][8][9]. With the development of the robotics, the robot manufacturers provide software for off-line programming, such as RobotStudio, which is a simulation and off-line programming software of ABB Company [10].…”

“…Most previous researchers typically focused on the mesh method for automated trajectory generation since such method is capable of generating trajectories on all types of complex workpieces [8,11]. In the mesh method, the mesh of the CAD model is generated at first, then the trajectory from the mesh points and normal vectors to the surface are found out according to graphics theories.…”

A parametric simulation model for HVOF coating thickness control

“…At the beginning of robotized thermal spray process modeling, some researchers worked on the spray path generation for robotized thermal spray coating application and the modeling method linking the path, thermal history of the workpiece, and coating thickness prediction. Candel and Gadow [21] developed a computer-aided trajectory generation method by using reverse engineering technology. Then they constructed a linking method between the impinging flame and the substrate physics performance by integrating the generated path into the finite element method (FEM).…”

Manufacturing engineering in thermal spraying by advanced robot systems and process kinematics

“…The points of the mesh are used as points of the robot TCP trajectory in the coating process. Robot trajectories for complex-shaped geometries can be generated with this method, as it was shown by Candel and Gadow (2009) for the case of a ship propeller. In such case, the mesh size in that direction is equal to the scanning step.…”