Optimization Of Process Parameters Of Aluminum Alloy Wheel Hub Spraying Pretreatment Based On Orthogonal Test

With the rapid development of world economy and the continuous improvement of people's living standard,car gets more and more widely used,and gradually popularized.Aluminum alloy wheel hub is widely used in automobile industry because of its safety,comfort,beauty,energy saving,light weight,corrosion resistance and good balance.In the production of aluminum alloy wheel hub,spraying is the last line,and it is a process with the highest value.Spraying is crucial to improve the aesthetic feeling and corrosion resistance of aluminum alloy wheel hub.However,the corrosion resistance of aluminum alloy wheel hub is directly related to the spraying pretreatment process.Spraying pretreatment processes include degreasing process,surface conditioning process,passivating process and water washing process,etc.Each process involves multiple process parameters.If the process parameters are not controlled properly,the pretreatment effect of aluminum alloy wheel hub can be directly affected.Furthermore,the spraying effect and corrosion resistance of aluminum alloy wheel hub can be affected.That is to say,the product quality of aluminum alloy wheel hub will be affected.At present,there are few researches on optimizing the parameters of aluminum alloy wheel hub spraying pretreatment.Most of the production is based on experience,which cannot improve the quality of aluminum alloy wheel hub.This research applied the orthogonal test method,to carry outoptimization research of process parameters of Aluminum Alloy Wheel Hub spraying pretreatment.It is of some theoretical significance and application value to guarantee the quality of aluminum alloy wheel hub products.In this study,orthogonal test study was conducted on three key processes which is degreasing,surface conditioning and passivating,to research optimization of process parameters of each process.And on this basis,the verification test analysis,verifythe good effectof the research results to the corrosion resistance of aluminum alloy wheel hub.Orthogonal test results show that: The primary and secondary order of the four influencing factors of degreasing process is free alkalinity,time,spray pressure and temperature,and the optimized process parametersrespectively for 1%~3%,90 s ~120s,0.10 MPa~0.13 MPa,50 ? ~60 ?;The primary and secondary order of the four influencing factors of surface conditioning process is free acid acidity,time,spray pressure and temperature,and the optimized process parametersrespectively for 4%~10%,60s~90s,0.10MPa~0.15 MPa,room temperature;The primary and secondary order of the four influencing factors of passivating process is electrical conductivity of tank liquor,spray pressure,time,and temperature,and the optimized process parametersrespectively for 550?s/cm~650?s/cm,0.06 MPa~0.09 MPa,60s ~90s,room temperature.The verification test results show that the optimized pretreatment process parameterscan ensurethe corrosion resistance of aluminum alloy wheel hub is met or superior to the product standard requirements.