Through the description of complex parts structure and reverse engineering. This paper mainly studies the application of reverse engineering technology to the point cloud data detection of complex parts, and uses Geomagic control to complete the size comparison of diffuser impeller of complex parts, and verifies the size error transfer law. The results show that the average positive dimension deviation of the diffuser impeller is 0.4212mm, and the average negative dimension deviation is -0.7269mm. The actual dimension deviation in all directions is larger than the theoretical calculation, which is mainly due to the larger size of the diffuser parts and the larger temperature difference between the powder bed and the parts.
Through the calculation of machining allowance, the machining allowance of upper and lower plane and inner cavity are 1.68mm and 3.08mm respectively. Combined with the results of the diffuser size deviation, through the calculation of the corresponding size error, the verification of the size transfer law is completed, and the corresponding error compensation path is determined. The size correction of the corresponding parts of the diffuser impeller is completed by using magics19, and the scanning comparison is carried out again to obtain the qualified SLS prototype of the diffuser. Finally, the machining allowance is calculated.