Extrusion Speed Dual-channel Extrusion Affect The Microstructure And Properties Of 7003 Aluminum Alloy

7003aluminum alloy is a kind of high-strength and high-hardness aluminum alloy,which posseses fine processing property and usability property.So it has become a key point in recent years on how to improve the properties of the materials and update potential materials to apply to other fields.In this paper, we adopt one of the SPD(Severe Plastic Deformation) technology methods D-ECAP(Double Channel Equal Channel Angular Extrusion)in the point of simulating study and experiment to do some research on some effects on the microstructure and mechanical properties of7003aluminum alloy in different extrusion speeds.Based on the previous research, the maximum loading force、the metal flow velocity、the distribution of stress and strain in different speeds is simulated and analyzed by3D-deform software. Simulation results show that when the extrusion speed increase,the load force has a tendency of first increases then decreases,;and also the faster the extrusion speed,the unevener the strain distributes;the distribution of stress is roughly same at different extrusion speeds.;with the increase of extrusion passes,the phenomenon of the uneven stress distribution has a certian improvement.By the simulation results,we set the experiment scheme,and complete the one and two pass D-ECAP experiments in different speeds,and then the microstructure and mechanical property are carried out on the extrused samples. The results show that the strength、the hardness and the strain all improve after one and two pass deformation, In the present experimental conditions,use extrusion speed35mm/min for one pass deformation and25mm/min for two pass deformation,the sample show a larger strength; the atom inside the sample has a tendency to transition to a metastable state crystal plane,the phenomenon is more obvious when the extrusion increase;The second phase will grow in numbe, the size will be lager and the phenomenon of dispersive distribution will weaken;Both in the one pass deformation and two pass deformation,there is a critical deformation speed,the strength of the sample will decrease in a certain extent when exceed this speed.