Research On Torsion Forming Technology Of Aluminum Alloy Industrial Fan Blade

With the modernization of components toward the lightweight and high-performance direction,the structure of hollow aluminum blades are more and more widely used in the industrial fan blade.As the blade geometry is more complex and there are often many internal ribs structure,the use of conventional torsion forming process required forming force larger and prone to rebound is too large,instability wrinkling and other defects,the above problems increase the difficulty of blade torsion forming process.Therefore,the study of aluminum alloy blade with the reinforcement of the overall torsion forming new technology is an urgent need in the field of research.This article to 6061 aluminum alloy fan blade torsion forming as the object of study,for enterprises in the production of the problems,launched the relevant technology research.The room temperature mechanical properties test of 6061 aluminum alloy was carried out to obtain the main mechanical properties and constitutive equations of the composites,which provides the material model for the following finite element analysis.The high temperature stress relaxation test of 6061 aluminum alloy was carried out to analyze the influence of pre-temperature,Pre-strain on the stress relaxation,the suitable parameter range of stress relaxation was obtained,which provided the basis for subsequent stress relaxation aging forming test.The technology of simple torsion and pretorsion and restretching is analyzed by finite element simulation,with determining reasonable and feasible process plan.According to the optimum process parameters determined by the simulation results,the verification test of the first torsion and re-drawing of the blade was carried out,the twist angle of the blade was accorded with the design minimum twist angle.The design of the simple torsion fixture and the experimental research on the stress relaxation forming of blade pre-torsion was carried out,by analyzing the effect of aging temperature and time on the springback of the torsion angle,the optimal aging temperature and time for the minimum torsion angle of the blade are obtained.In this paper,the following results are obtained: Two pre-torsional tension forming and pre-torsional stress relaxation aging processes are proposed.By the finite element simulation of the 6061 aluminum alloy blade torsion forming,the correct evaluation is taken,The pre-torsion and re-stretching process is adopted to obtain the torsion angle of the blade in accordance with the design requirements.The pre-torsion stress relaxation aging process is proposed.By controlling the aging temperature and time parameters,the blade twist angle is small.And the blade surface is not defective,no reinforcement instability phenomenon.The research results have been successfully applied to enterprises in the industrial fan blade torsion forming process,so as to solve the enterprise in the production of technical problems.