The Preparation Process Of 1060/AZ31/1060 Composite Board And The Growth Law Of Interface Diffusion Layer

Magnesium-aluminum composite material not only has good corrosion resistance of aluminum,excellent processing performance and aesthetic appearance,also has a lightweight magnesium,damping.Recently,revolving around the preparation and formation of interlayer have become investigative hot spot.Mg/Al composites are widely used in aerospace,automotive,computer,communications and other fields.This paper focus on the preparation of 1060/AZ31/1060 composite by the method of combining friction stir welding with rolling to obtain a better process parameters.For 1060/AZ31/1060 composite,the change regulation of flow stress during temperature deformation was analysed with the variaty of strain rate and deformation temperature and constitutive equation of composite was eatablished.Processing maps for hot working are developed on the basis of the hot-rolling process of composite.The effect of heat treatment technology on mechanical property,interfacial microstructure,interfacial compound formation and interfacial microhardness of composite were studied.For the rolling reduction rates of 88.5%,78.5%,66.9% and 57.4%,growth behaviour of 1060/AZ31/1060 composite interface were studied to establish different diffusion kinetic models.This thesis provided reference to the optimization of the prepartion technology and the control of interface of 1060/AZ31/1060 composite.The main results are as follows:?1?When the hot rolling thickness of 1060/AZ31/1060 composite is to some extent,the bigger pass reduation is more favourable for combining Mg with Al under the heart of composite withot cracking and the uniform grain size.When intermediate annealing temperature of 1060/AZ31/1060 composite is 430 ? and intermediate annealing time is keep around 10 min,better composite could be gotten.?2?The flow stress of 1060/AZ31/1060 composite keep flat or increase slightly with the increasing of strain capacity during hot compression tests.When the strain rates are 0.1s^-1 and 0.01s^-1,the flow stress increases sharply with the increasing of strain capacity at the initial stage and then the flow stress would keep stabilized after flow stress reaches a maximum.While the strain rates are 1s^-1 and 10s^-1,the flow stress also increases sharply at the initial stage and the flow stress keep a slowly increasing trend in later stage.?3?When the strain capacity is small??=0.1?,1060/AZ31/1060 composite should be processed within the strain-rate of 0.1s^-1,and the higher temperature is more favorable for forming in this domian.When the strain capacity is greater than 0.1,and the domains are suitable for hot working and the energy dissipation coefficients of them are relatively lager at lower temperatures?250 ??and higher strain rates(10 s^-1),lower temperature and lower strain rates(0.01 s^-1).With the increasing of strain capacity,the peak energy dissipation coefficient would gradually increase.With the decreasing of temperature,the energy dissipation coefficient would gradually increase in the lower strain capacity of domain.?4?When the annealing time was 2 h,the microhardness of interfacial diffusion layer for 1060/AZ31/1060 composite increased gradually with the increase of annealing temperature;When the annealing temperatures were 300 ? and 400 ?,the microhardness of interfacial diffusion layer increased with the increase of annealing time.?5?The thickness of interfacial diffusion layer for 1060/AZ31/1060 composite improved with increasing of the annealing time and when there is a balance between Mg and Al in the diffusion layer,its corresponding length is gradually increased.There are mainly second phase of ₁₇Al₁₂?Mg₂Al₃?Al₅Mg₁₁Zn₄, and Al₆Mn at the early heat treatment of 1060/AZ31/1060 composit.With the extension of the annealing time,Mg₃₂?Al,Zn?₄₉ phase appears and its amount gradually increased.?6?When the annealing temperature and time are constant,the thickness of interfacial diffusion layer gradually increases with the increasing of rolling reduction rates?57.4%-88.5%?.As a result of different rolling strain fields,the dynamics model formula of interfacial diffusion layer for 1060/AZ31/1060 composite is as follows:...