| The Ti/Al composite plate with excellent properties of both titanium alloy and aluminum alloy is one of the most popular metal composites.Due to the advantages of light weight,high temperature resistance,high thermal conductivity,high wear resistance,high corrosion resistance and high strength,Ti/Al composite plates have been employed in aerospace,petrochemical and automotive industries.Based on Abaqus finite element method(FEM),the finite element simulation on the corrugated-flat rolling(CFR)process of Ti/Al composite plates had been performed in this paper.The plastic deformation behavior of the composite plates during the rolling process had been researched,which can provide early guidance for subsequent rolling experiments.Then,the Ti/Al composite plates were prepared by the corrugated-flat cold rolling process,and the composite plates were annealed at a low temperature.The metallographic microscope and scanning electron microscope were used to observe the microstructure of the interface layer of the composite plate,the fracture of the tensile and shear specimens,and the interface of the bending specimen.The mechanical properties of the composite plates were tested by the micro-hardness tester and universal testing machine.The structure evolution and mechanical properties of Ti/Al composite plate were obtained through comprehensive analysis.The specific research contents are as follows:First,the corrugated-flat cold rolling model of the Ti/Al composite plate was simplified and established using a single variable method.Under different working conditions,the characteristics of the corrugated-flat cold rolling process and the reduction ratio s of the first-pass and second-pass were determined according to the rolling deformation behavior and the comparison with the ordinary flat rolling.This can provide early guidance for subsequent experiments.Secondly,the Ti/Al composite plates were fabricated by the corrugated-flat cold rolling process The results showed that the interface was a good combination and had the best comprehensive performance at the first-pass reduction ratio of 40%.The interface was tightly combined without cracks.The corrugated interface can promote the extension of titanium and increase the bonding area of these two substrates.The average ultimate tensile strength(UTS)of the corrugated composite with the first-pass 40% reduction ratio was 269 MPa,which was greater than the theoretical value of 238 MPa,and the average elongation was 17.5%.The average shear strength was 61 MPa and the average peel strength was 19.85 N/mm.The second-pass rolling process was carried out on the one-passed composite plate with a 40% reduction ratio,and it was found that the composite plate had the largest bonding strength and the best overall performance when the total reduction ratio was 60%.After two passes rolling process,the original corrugated interface was extended and the interface was relatively straight.The average UTS of the total reduction ratio of 60% was 382 MPa,which was greater than the theoretical value of 304 MPa.And the average elongation was 10.8%.The Ti/Al composite plate with a total reduction ratio of 60% was subjected to a stress relief annealing treatment at 300? for 0.5h.After annealing,the thickness of the diffusion layer of the composite plate increased slightly,from 2.0?m to 3.5?m.The average UTS of the annealed composite plate was 301 MPa,which was about 21% lower than that of the as-rolled plate.While the elongation had increased from 10.8% to 19.1%,a growth of more than 76.8%.After annealing,the shear strength increased slightly,and the average shear strength increased from 98 MPa to 101 MPa.Compared with the as-rolled composite plate,the annealed composite board had a better overall performance. |
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