The Research On Elastic Deformation Control Technology For NC Machining Titanium Alloy Integral Impeller

As the key components of aero engine, the machining quality and precision of theintegral impeller are related to the performance of aero engine. Integral impeller is machinedmainly by using Five-axis CNC machine tools, while integral impeller made by titanium alloynot only have machining difficulties, but also have problems such as cutting tool wear, easy toproduce elastic deformation, flutter and low machining efficiency and so on. Aiming at theproblems of the fine machining of integral impeller of titanium alloy, for example, lowmachining precision, poor surface quality, caused by blade elasticity, this paper conducts aresearch and puts forwards the mixed cutter path strategy of semi-finish and finish andoptimization method of fine machining feed rate based on blade stiffness to reduce themachining errors greatly, and improve the surface quality. The concrete research contents areas follows.(1) The structure characteristics and the machining difficulties of integral impeller oftitanium alloy are analyzed. Also designing machining schemes for the integral impeller, andcarrying on the simulation of NC machining of integral impeller based on VERICUT areincluded.(2) A finite element model of single integral impeller blade precision is set up to analyzethe cutting force, the cutting position and the machining allowance’s influence on the elasticdeformation of the blade, and according to the conclusion, two methods of reducing elasticdeformation of integral impeller blade machining of complex curved surface are proposed:semi-finish and finish mixed cutter path strategy, optimization of cutting parameters.(3) Methods of fine machining feed rate based blade stiffness are presented, reducing themachining errors, improving the surface quality and improving the processing efficiency atthe same time. The effectiveness of the proposed method is verified by means of integralimpeller single blade contrast experiments.(4) It has carried on the machining experiment of integral impeller of titanium alloy andanalyzed the quality of machined surface and errors.Through cutting experiment of single blade and machining experiment of integralimpeller of titanium alloy show that semi-finish and finish mixed cutter path strategy andoptimization method of fine machining feed rate based on blade stiffness can reducemachining errors, improve the surface quality and improve the processing efficiency at thesame time.