Negative thermal expansion Y2Mo3O12 particles reinforced AgCuTi composite filler for brazing Cf/SiC and GH3536

A novel composite brazing alloy by introducing negative thermal expansion Y2Mo3O12 particles into AgCuTi alloy was developed to alleviate the residual stress of C-f/SiC-GH3536 joint. The negative thermal expansion behavior of Y2Mo3O12 material and its effects on the shear strength of brazed joints were investigated. The strong negative thermal expansion behavior of Y2Mo3O12 material greatly reduce the coefficients of thermal expansion of composite filler, which can greatly alleviate the residual stress of C-f/SiC-GH3536 joint. In addition, the interface structure has been greatly optimized, leading to enhanced bonding strength. The maximum shear strength of C-f/SiC-GH3536 joints reached similar to 42 MPa after added 3 wt% Y2Mo3O12, which was 1.6 times higher than that of original joints. This study shows that Y2Mo3O12 can maintain its strong negative expansion characteristics during the brazing process, which may provide a new idea to solve the hygroscopicity of Y2Mo3O12.

Automated summary

A novel composite brazing alloy was developed by introducing Y2Mo3O12 particles with negative thermal expansion into AgCuTi alloy to alleviate the residual stress of C-f/SiC-GH3536 joint. The strong negative thermal expansion behavior of Y2Mo3O12 material greatly reduced the thermal expansion coefficients of the composite filler, leading to the reduction of residual stress and the enhanced bonding strength of the joint.