Research On Warm Incremental Forming Of AZ31B Magnesium Alloy Sheet

Magnesium alloy has excellent performance such as light weight,high strength,electromagnetic noise shielding and creep resistance and other characteristics.in recent years,it`s began to replace aluminum and steel and widely used in automobile,aircraft,weapons,computer manufacturing,and other products.However,most of the magnesium alloy was difficult to forming at room temperature due to its structure.but some studies showed that the forming performance of magnesium alloy is improved significantly at high temperature.in terms of processing methods,the traditional machining method is complex and time consuming.In recent years,the single point incremental forming has been taken seriously by scholars at home and abroad because of the advantages of its without mold or only simple mold,and small forming force.so the incremental forming technology has a great influence to the development of magnesium alloy.In this paper,taking AZ31 B magnesium alloy sheet as the research target,carrying on the study on the warm incremental forming.The processing are analyzed in theory by using the software ABAQUS,analyse the influence of process parameters on single point incremental forming.this paper suggests a feasible method for incremental forming experiment with liquid medium heating,and builds a special platform to carry on the experiments,and explored the basic technology of the warm incremental forming of magnesium alloy sheet: the suitable temperature and the forming limit,and study the influence of parameters such as the forming angle,feed and spindle speed and other parameters.The main research contents are shown as follows:(1)The experiment of AZ31 B magnesium alloy experimental plate was carried out to determine the composition of the sheet and the stress-strain curves and other performance parameters at different temperatures,which provided the basis for setting the material properties in the simulation by ABAQUS.(2)Analysis of the gradual forming mechanism AZ31 B alloy sheet based onnumerical simulation.The stress and strain are analyzed layer by layer,because of the complexity of forming process.Study the variation of stress strain when different parameters change,so as to choose suitable technological parameters in practical production.(3)In this paper,a kind of progressive forming method with liquid medium heating is proposed,and did lots of experiments by the specified platform.The results showed that the method of heating by liquid medium is effective.Meanwhile,studied the forming limit on the different thickness of the sheet,we can design the forming angle experiment to determine the forming limit of different thickness sheet.At the same time,using the KISLER force measuring equipment in the experiment,the forming force of each direction in the forming process was measured and analyzed,and concluded the characteristics of forming force during processing.(4)The effect of parameters on the quality of the formed parts was studied.The experiences were carried on by change the forming angle,layer feed,spindle speed and other parameters.The results showed there were two forms:wall bulge and edge springback,and edge precision accuracy is better than the wall.The influence of the different parameters on the quality of the formed part and the incidence of multiple factors on the precision of the forming part are obtained.