| SiC ceramic has the characteristics of high temperature resistance,wearability,antioxidant,etc.TC4 alloy has a high strength,toughness and other characteristics.Therefore,achieving an effective connection of the two materials,can both be used for manufacture of complicated mechanical assemblies,but also improve the high temperature resistance performance of connectors.However,there are some difficulties in brazing these two materials since their difference in physical and chemical properties.One of the mostly widely used filler metal for these two materials is Ag-based brazing filler metal.Nevertheless,consumption of a large amount（50 wt.%）of the noble metal,Ag,in the brazing filler is the main disadvantage of these brazing filler metal.In this paper,two kinds of amorphous filler metal were designed and prepared,which cut costs dramatically.Besides,amorphous filler metal was used for these two materials.Brazing joints were marked as TC4/B-Ti0.46-Six/SiC and TC4/B-Ti0.55-Six/SiC（x=0%,0.5%,1%,2%）.The morphology,structure,components,thermodynamic characteristics,and wettability of amorphous filler metal were investigated.Combining the experimental results of brazing joints,the influence of adding Si and the formation mechanism of brazing interface were also analysised.In this paper,(Ti0.46Cu0.14Zr0.27Ni0.13)1-x Six and（Ti0.55Cu0.20Zr0.15Ni0.10）1-x Six（x=0%,0.5%,1%,2%）amorphous filler metal were designed and prepared,abbreviated B-Ti0.46-Six and B-Ti0.55-Six（x=0%,0.5%,1%,2%）.Among the two brazing filler metal,the glass forming ability（GFA）of the filler metal without Si was worst,and the GFA of the filler metal with 0.5%Si was best.With the component of Si from 0%to 0.5%,the?Tx of B-Ti0.46-Six filler metal increased by 22℃,as well as Trg increased by 8.7%.Besides,with the component of Si from 0%to 0.5%,the?Tx of B-Ti0.55-Six filler metal increased by 22℃,as well as Trg increased by 7.9%.The addition of 0.5%Si into the filler metal could increase both?Tx and Trg,indicating that the GFA of the filler metal was promoted by adding Si.Also,the filler metal with0.5%Si exhibited a best wetting ability.The highest shear strength of B-Ti0.46-Six filler metal at room temperature was 80MPa when adding 0.5%Si.The microstructure of TC4/B-Ti0.46-Si0.5%/SiC joint was:TC4/（α+β）-Ti/TixSiy+Zrx Siy/α-Ti+β-Ti/Ti（s,s）+TixCuy+Cux Zry/Ti C+Zr C+Tix Siy+Zrx Siy/SiC.The typical microstructure of the B-Ti0.46-Six（0%,0.5%,1%）joints was:TC4/（α+β）-Ti+Ti2Cu/Tix Siy+Zrx Siy/α-Ti+β-Ti+Ti2Cu/Ti（s,s）+Tix Cuy+Cux Zry/Ti C+Zr C+Tix Siy+Zrx Siy/SiC.Tests showed that the interfacial reaction layer at the side of SiC ceramic and the morphology and distribution of brittle compound exerted an influence on shear strength.The dispersively distributed brittle compound which could improve strength and toughness of joints by dispersion strengthening effect,and the interfacial reaction layer with appropriate thickness which could reduce residual stresses were formed in joints when adding appropriate Si to brazing filler metal.The highest shear strength of B-Ti0.55-Six filler metal at room temperature was102 MPa when adding 0.5%Si.The structure of TC4/B-Ti0.55-Si0%/SiC joint was:TC4/（α+β）-Ti/TixSiy+Zrx Siy/α-Ti+β-Ti/Ti（s,s）+TixCuy+Cux Zry/Ti C+Zr C+Tix Siy+Zrx Siy/SiC.The typical interfacial microstructure of TC4/B-Ti0.55-Si0.5%/SiC joint was:TC4/（α+β）-Ti+Ti2Cu/Tix Siy+Zrx Siy/α-Ti+β-Ti+Ti2Cu/Ti（s,s）+Tix Cuy+Cux Zry+Ni11Zr9/Ti C+Zr C+Tix Siy+Zrx Siy/SiC.Thetypicalinterfacialmicrostructureof TC4/B-Ti0.55-Six/SiC（x=0.5%,2%）jointswas:TC4/（α+β）-Ti+Ti2Cu/Tix Siy+Zrx Siy/α-Ti+β-Ti+Ti2Cu/Ti（s,s）+Tix Cuy+Cux Zry/Ti C+Zr C+Tix Siy+Zrx Siy/SiC.ComparedwithTC4/B-Ti0.46-Si0.5%/SiCjoint,TC4/B-Ti0.55-Si0.5%/SiC joint possessed a higher shear strength. |
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