Study On Deformation Law And Interface Combination Of Ti/Mg Multi-layer Rolled Composites

TA1/AZ31B/TA1 composite material with the low density of magnesium,high stiffness ratio,good damping,high corrosion resistance and high temperature impact resistance of titanium.It has wide application in aerospace,submarine,automobile,chemical and other industries.In this paper,AZ31 B and TA1 were studied,and TA1/AZ31B/TA1 layered composites were successfully prepared by rolling composite method.The interface structure and microstructure of TA1/AZ31B/TA1 composites were analyzed by optical microscopy(OM),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS).The interfacial bonding mechanism,The rolling deformation law,heat treatment process on its microstructure and its bending deformation behavior of TA1/AZ31B/TA1 layered composites was studied.The following research results are obtained:After rolling composite,the interface structure of TA1/AZ31B/TA1 lamellar composite was wavy,and the curves of Ti element and Mg element at the interface were vertically distributed without diffusion.After 5 successive rolling deformation TA1-AZ31 B undulate interface,with the increase of rolling passes,gradually increasing amplitude of the wavy lines,combined with more closely,5 times after rolling,Ti and Mg element in the interface junction happened a small amount of Mg and Ti atomic migration into "X" shape distribution,and its interface still is wavy,have the feature of mechanical mesh;After heat treatment,the change of interface morphology is not obvious.After the first pass rolling,the deformation of AZ31 B layer is 75.59% and TA1 layer is 1.04%,the deformation of AZ31 B layer is dominant.With the increase of rolling track,the deformation of TA1 layer gradually increased to 8.33%,while the deformation of AZ31 B layer gradually decreased and finally leveled off.The rolling deformation of the composite material is changed from AZ31 B to TA1 layer and AZ31 B layer.After heat treatment of TA1/AZ31B/TA1 lamellar composites,the microstructure of TA1 layer did not change significantly.During the heat treatment process,the microstructure of AZ31 B layer underwent static recovery and recrystallization,and the grains were equiaxial crystals with uniform distribution.The tensile strength of TA1/AZ31B/TA1 laminates decreases with the increase of temperature and does not change significantly with the increase of time.The tensile mechanical properties of TA1/AZ31B/TA1 laminates are the best at 450℃×2h.The shear strength first increases and then decreases with the increase of heat treatment temperature,reaching a maximum value of 86.64 MPa at 450℃.With the increase of time,the shear strength first increases and then decreases,reaching a maximum value of 86.64 MPa at 2h.The optimal heat treatment process condition is obtained as follows: 450℃×2h.The TA1/AZ31B/TA1 layered composite material has a certain thickness.During bending deformation,the outer TA1 layer is subjected to tensile deformation,while the inner TA1 layer is subjected to compression deformation.With the increase of bending Angle,the necking phenomenon of the outer TA1 becomes more and more obvious,The inner TA1 compresses and deforms,and the amount of free extension to both sides gradually increases.When the bending Angle is 120°,layer ta1-az31 b is stratified,and when the bending Angle is 150°,layer AZ31 B appears a crack across the matrix,reducing its bending strength.The maximum bending angle is 90° and the bending strength is 349.68 MPa.