Development, Of The Cbc And Cmc Metal Laminated Composite

The essay contains three parts,the first one is about the research of the CBC.CBC(Cu/BMn40-1.5/Cu)is a kind of laminar composite,which has specific elastic property and used in the military parts.In the expriment,the melting process of the BMn40-1.5 alloy was choosen and optimal processing technic of the CBC was discussed,also the tensile strength,electric conductivity and elastic ratio of the CBC was studied. The second part was about the delamination of molybdenum in Cu/Mo/Cu electronic material.To improve the technology,the problem of delamination was solved and the rate of finished products was increased. The recrystallization of molybdenum was observed by OM,the recrystal mechanism was also studied.In the third part,the specil variable rule of the structure was observed by the OM and SEM after shearing deformation by the guillotine.A method was proposed to refine grains in metal sheets by using shearing deformation and annealing sample at suitable temperature to obtain ultra fine grains.The results showed that:(1)When melting the BMn40-1.5 alloy,good property would be gained by prolonging the time of refinement and using the solidifying exhaustion in magnesite melting pot for vacuum melting,which could be good for the hot rolling with copper plate.(2)When compound by hot rolling,2.8mm thick copper plate with 3mm thick BMn40-1.5 alloy could be combined great.After rolling to products,the thickness ratio could reach 1:1.22:1,which was suitable for the practical application.(3)As the increase of cold rolling rate,the elastic ratio of the BMn40-1.5 alloy and CBC alloy increased gradually.But as the increase of annealing temperature,the elastic ratio of the CBC alloy was no change almost.(4)After cold rolling,the grains of CBC alloy were one kind of deformation grains,which were highest tensile strengh and lowest electrical conductivity.When annealing at 400℃temperature,the recrystal grains could be observed in copper layer.When anneaing at 800℃temperature,the recrystal grains grew up completely.As the increase of the annealing temperature,the tensile strengh decreased gradually and the electrical conductivity raised first and then fell down,which the highest value could be studied after annealing at 400℃.(5)The difference between measured value and theoretical value of the CBC alloy was studied.The results show that the measured electrical conductivity was higher than the theoretical value but the elastic ratio was no much difference with the theoretical value.We could use superposition method to predict the elastic ratio of the CBC alloy.(6)The rate of finished products was better after the Mo plate annealed at 1150℃to produce Cu/Mo/Cu,but not the best.After increasing the hot rolling compound temperature of Cu/Mo/Cu from 850℃to 950℃,the rate of finished products can reach to 90%,could satisfy the production.(7)Dynamic recovery was the main softening mechanism when the Mo was hot worked under the recrystallization temperature.(8)Such a phenomenon that we called "fibre structure grew width" could be observed in the recrystallization of Mo.Two recrystal mechanism could be studied,that were mechanism of crystal boundary migration and subgrain coarsing nucleation.(9)Some twin crystals and honeycomb structures would be observed in the shear plane of the C72500 alloy and many kinds of deformation mechanism were studied.When annealed at 550℃for 2 hours, recrystal gains were observed in the shear plane.Especially the side received the cut of guillotine,the size of recrystal gain was much thinner.(10)Based on this phenomenon,associating with asynchronous rolling and Confined Strip Shearing technology,a method was proposed to refine grains in metal sheets by using shearing deformation and annealing sample at suitable temperature to obtain ultra fine grains.