As we all know, ceramic materials have excellent high temperature resistance, wear resistance, corrosion resistance, low density, good insulation characteristics, and have broad application prospects in the automotive, military, electronics, aerospace and other fields.
At the same time, the brazing technology of ceramics and metals is one of the key technologies for the development and application of cermet materials. According to the application requirements, an effective connection method is selected to connect the ceramic and metal to obtain the ceramic-metal composite component, which can combine the advantages of the two, give full play to the excellent performance of the ceramic material and broaden its application range. Therefore, it is necessary to understand the difficulties of ceramic and metal brazing.
Ceramic and metal brazing is a special welding technology, its difficulties mainly include the following aspects:
Material matching problem: Ceramic materials generally have higher hardness and brittleness, while metals have better toughness and weldability. Therefore, the matching problem of the two materials needs to be taken into account when selecting the brazing filler metal to ensure the brazing quality.
Heat conduction problem: Due to the large difference in thermal conductivity between ceramics and metals, heat is easily lost between the two when brazing at high temperatures, resulting in poor brazing quality.
Oxidation problem: There is usually an oxide layer on the surface of ceramic materials, which will affect the wettability and deposition properties of the brazing filler metal, and thus affect the brazing quality.
In view of the above difficulties, the following solutions can be adopted:
Select the appropriate filler metal: According to the characteristics of ceramic materials and metal materials, the suitable brazing filler metal is selected for brazing, such as the use of silver solder, copper solder and so on.
Optimize brazing process: By adjusting brazing temperature, brazing time, brazing shape and other factors, the brazing process is optimized to improve the heat conductivity and brazing quality.
Take appropriate pretreatment measures: The surface of ceramic materials and metal materials were cleaned, polished and heated to remove the surface oxide layer and improve the wettability and deposition performance of the filler metal.
Vacuum brazing technology is adopted: Vacuum brazing technology can effectively control the oxidation problem and improve the brazing quality. At the same time, the technology can also control the shape and size of the brazing, and further improve the quality of brazing.
The above is a brief introduction to the difficulties and improvement methods of ceramic and metal brazing. If you want to learn more about ceramic and metal brazing, Insealing can provide you with more information. Please contact us with no hesitation.