Regulation of Interface Reaction between Negative Expansion Material and AgCuTi Active Filler
Negative expansion material can effectively alleviate the high thermal expansion of metal.Usually,the interface reaction between the negative expansion material and the active metal can realize the interface bonding between the negative expansion material and metal base.However,it is difficult to control the degree of interfacial reaction between them.Excessive interfacial reaction will damage the structure of the negative expansion material and make it lose its negative expansion property.In this paper,a carbon barrier layer was constructed on the surface of negative expansion material by one-step hydrothermal method.This method has the advantages of simple and low-price,and has a good application prospect.Furthermore,pure AgCuTi filler,Sc2W3O12 reinforced AgCuTi composite filler and carbon coated Sc2W3O12 reinforced AgCuTi composite filler were used for vacuum brazing of C/SiC composite and GH3536 at 860℃/10 min,respectively.The results showed that the prepared carbon barrier layer can effectively alleviate the interfacial reaction between the negative expansion material and the AgCuTi filler.It not only reduces the thickness of the reaction layer,but also ensures the interface bonding.The shear strength of joints prepared by Sc2W3O12@C reinforced AgCuTi composite filler is up to 72 MPa,which is 1.3 times higher than that of Sc2W3O12 reinforced AgCuTi composite filler and 2.5 times higher than that of AgCuTi filler.
万方数据
维普
