Study Of The Process Optimization And Scan Path In Laser Cladding

Laser cladding process is a new high-technology. It has many advantages such as cutting the cost, decreasing the leading time, improving the surface capability, prolonging lives of the parts, obtaining graded function and being friendly with environment. At present, this technology has being applied to the industry fields such as part repair and manufacture, and gained good effectiveness in practice.Due to many theoretical and practice questions involved in this process which have not been solved, there are many restrictions on the application of laser cladding process.In order to improve the dimensional accuracy of parts and surface quality , the realization of automation in laser cladding, the optimization of processing parameters and the realization of the scan path which are two very important issues in the process of laser cladding are researched in this paper, which is of great significance for laser cladding forming part of the quality control.Due to the complexity of the process of laser cladding, in this paper, combination of Back Propagation(BP)neural network and Particle Swarm Optimization (PSO) algorithms were used to optimize process variables during the laser cladding. Firstly, BP neural network model was developed to express the relationship between the clad process variables and the clad parameters (the width,height of clad bead). Then, PSO algorithm was used to grabble the suitable values of the process variables in the target region. A software system was designed under the VC++ platform, Realize the optimization of process parameters.In addition, this paper studied the planning of laser scanning path, and eleborated a series of methods that included building 3D CAD model,scanning path realization and so on, especially for the 3D model slice algorithm and straight-line bidirectional scan algorithm, then presented the planning of scanning path according to the method of distance judging, and developed the corresponding program. For the motion system of robot, the data exchange from the designed software system to robot was studied, which realized the data of scanning path transformation in order to control the movement of the robot.By experimental point of view, the paper verified the implementation of the optimization and scan path. Single-pass cladding experiments and scan path filled experiments are carried out with a semiconductor laser on the QT600-3 surfaces.The experimental clad parameters with the process variable values calculated by this optimization method were coincident well with the expected ones. Minimum error is 1.7%, maximum error is 9.2%, which indicated that the optimization method is feasible and can help to obtain the expected laser clad quality;The communication between software and the robot is built to reach the purpose of the scan path generated by using software to control the robot movement. The laser cladding forming test shows that the method is feasible both from the simulation and experimental verification of the implementation of directional scanning path.