Development Of CAM Softwar For Laser Metal Deposition Based On OCCT

Laser metal deposition(LMD)is one of additive manufacturing methods,which has a history of almost 20 years.Rapid development has been made in the processing of this field.However,the quality of CAM software cannot catch up with the speed of LMD processing development.There exists a disconnect between software and LMD processing,resulting in the precision,efficiency and part shape of LMD processing are restricted by software.So,in this paper,a CAM software,especially for LMD processing,is developed.Moreover,the LMD experiment was performed to qualify the function of CAM software.In order to improve the robustness and efficiency,C++,Qt and Open CASCADE Technology(OCCT)are utilized to develop the GUI and main functions.There are 5 main functions in LMD CAM software,which include model import,model display,slicing,scan-path planning and robot code transforming.The last three functions are related directly to LMD processing.So,specialized algorithms are developed for them.STL file import is realized.STL model is transformed into B-rep model.So that the model can be displayed and sliced by means of OCCT.B-rep model is showed in graphics display window,in which translation,rotation and scaling of view is allowed.Slicing and scanning path planning are core functions.The equidistant slicing method is used and realized by common boolean operation in OCCT.Scanning path planning algorithms are divided into two methods based on part characteristics.Contour and hatch path are adopted in thick-walled parts,which are realized by section boolean operation in OCCT.Standard and helical scanning path planning algorithms are adopted in thin-walled parts.A thin-walled part can be made with the laser turned on only once by the helical scanning paths.Coaxial powder feeding codes and paraxial powder feeding codes transformation algorithms are adopted based on 6-axis robots.Key orders of KUKA off-line programming are instructed.The deduction of Euler angles of laser head by Rodrigues' formula is elaborated.Finally,thin-walled parts,which are made of 316 L or Al Si10 Mg,are manufactured with the CAM software.The algorithms in the software are qualified.