Ag-Cu-In-Ti low-temperature filler was used to braze the diamond and copper,and the effects of brazing temperature and soaking time on the microstructure and mechanical properties of the joints were investigated.In ad...Ag-Cu-In-Ti low-temperature filler was used to braze the diamond and copper,and the effects of brazing temperature and soaking time on the microstructure and mechanical properties of the joints were investigated.In addition,the joint formation mechanism was discussed,and the correlation between joint microstructure and mechanical performance was established.Results show that adding appropriate amount of In into the filler can significantly reduce the filler melting point and enhance the wettability of filler on diamond.When the brazing temperature is 750°C and the soaking time is 10 min,a uniformly dense braze seam with excellent metallurgical bonding can be obtained,and its average joint shear strength reaches 322 MPa.The lower brazing temperature can mitigate the risk of diamond graphitization and also reduce the residual stresses during joining.展开更多
The SiC/SiC joints were vacuum brazed at 700℃,740℃,780℃and 800℃for 10 min respectively,using Ag-Cu-In-Ti active filler alloy.The microstructure and joining strength of the joints were characterized by electron pro...The SiC/SiC joints were vacuum brazed at 700℃,740℃,780℃and 800℃for 10 min respectively,using Ag-Cu-In-Ti active filler alloy.The microstructure and joining strength of the joints were characterized by electron probe X-ray microanalyser(EPMA),energy dispersive spectroscopy(EDS),transmission electron microscopy(TEM)and four-point bending strength test.The interface of the joints was composed of three parts:SiC substrate,reaction layer and filler alloy.A representative microstructure of the reaction layer:In-containing layer/TiC layer/Ti5Si3 layer was found from the TEM image.The forming of the In-containing layer could be attributed to the crack or delamination of SiC/TiC interface.The In-containing layer intensified the coefficient of thermal expansion(CTE)mismatch of SiC and the reaction layer,and affected the joining strength.With the increase of the reaction layer’s thickness,the joining strength firstly increased,then declined,and the maximum four-point bending strength reached 234 MPa.展开更多
基金National MCF Energy R&D Program(2019YFE03100400)。
文摘Ag-Cu-In-Ti low-temperature filler was used to braze the diamond and copper,and the effects of brazing temperature and soaking time on the microstructure and mechanical properties of the joints were investigated.In addition,the joint formation mechanism was discussed,and the correlation between joint microstructure and mechanical performance was established.Results show that adding appropriate amount of In into the filler can significantly reduce the filler melting point and enhance the wettability of filler on diamond.When the brazing temperature is 750°C and the soaking time is 10 min,a uniformly dense braze seam with excellent metallurgical bonding can be obtained,and its average joint shear strength reaches 322 MPa.The lower brazing temperature can mitigate the risk of diamond graphitization and also reduce the residual stresses during joining.
文摘The SiC/SiC joints were vacuum brazed at 700℃,740℃,780℃and 800℃for 10 min respectively,using Ag-Cu-In-Ti active filler alloy.The microstructure and joining strength of the joints were characterized by electron probe X-ray microanalyser(EPMA),energy dispersive spectroscopy(EDS),transmission electron microscopy(TEM)and four-point bending strength test.The interface of the joints was composed of three parts:SiC substrate,reaction layer and filler alloy.A representative microstructure of the reaction layer:In-containing layer/TiC layer/Ti5Si3 layer was found from the TEM image.The forming of the In-containing layer could be attributed to the crack or delamination of SiC/TiC interface.The In-containing layer intensified the coefficient of thermal expansion(CTE)mismatch of SiC and the reaction layer,and affected the joining strength.With the increase of the reaction layer’s thickness,the joining strength firstly increased,then declined,and the maximum four-point bending strength reached 234 MPa.
