Research On The Rolling And Heat Treatment Process Of 7085/7085+TiC Aluminum Alloy

As a kind of new generation aluminum alloy,7085 alloy has high quench sensitivity and specific strength,which has been widely used in the fields of the aerospace and automotive.In this paper,7085 aluminium alloy was chosen as the object of study.The effects of hot rolling reduction and deformation temperature on the microstructures and properties of 7085 aluminium alloy were studied by means of OM、DSC、XRD、SEM and TEM.The effects of multiple regression and aging treatment on the microstructures and properties of 7085 aluminum alloy were investigated.On the basis of the results of rolling and heat treatment tests,the microstructure refinement mechanism and wear resistance of TiC/7085 aluminum matrix composites were studied.The research results showed as follows:(1)With the increase of hot deformation reduction,the recrystallization and the dislocation density increased gradually,meanwhile the grain size became small one after solid solution and aging treatment,which leaded to an increase of the mechanical properties of alloy.And the intergranular corrosion resistance decreased.With decreasing of the hot rolling temperature,the recrystallization degree of the alloy and the grain size increased gradually,which the mechanical property of the alloy reduced.The optimal process parameters were430℃ of deformation temperature and 80% of rolling reduction.(2)The mechanical property of alloy could be improved by appropriate heat treatment process.When the heat treatment process parameters included pre-aging temperature of 117℃ and pre-aging time of 6h,final aging temperature of 167℃ and final aging time of 9h,7085 aluminum alloy showed an excellent combination property,including the tensile strength of512.87 MPa and the elongation 12.65% respectively.Compared with the RRA treatment and the T6 aging treatment,the tensile strength and corrosion resistance were improved.But creep resistance decreased slightly.With the increase of regression times,the strength of the alloy decreased gradually,and the corrosion resistance was similar to that of T73.But the creep resistance was better than that of T73 treatment.(3)TiC nanoparticles added into 7085 alloy effectively broke ?l-A dendrite and refined grain.TiC nanoparticles played an important role in the nucleation of composite materials.During deformation of the alloy,TiC nanoparticles inhibited effectively dislocation migration,which specialization hindered.Tic particles were uniformly distributed in the aluminummatrix by the subsequent heat treatment.With the increase of Tic particles content,the wear resistance decreased gradually.The research results showed that the wear rate of7085/7085+TiC alloy decreased gradually with the increase of speed at room temperature.With increasing of the loads,the wear rate of the two materials increased gradually.But the wear resistance of TiC/7085 aluminum matrix composite was better than that of the 7085 aluminum alloy.