Jointing Betwwen Ceramic Parts and Metal Parts
Ceramic parts have excellent properties such as high temperature resistance, high strength, high hardness, wear resistance, oxidation resistance, and corrosion resistance. They can be used in harsh conditions such as high wear, strong corrosion, and high temperature for a long time. However, ceramic parts have high brittleness and high hardness, the cost of processing complex shapes or large-size products is very high; metal parts have excellent room temperature strength, toughness, electrical conductivity and thermal conductivity, and the processing difficulty and cost are much lower than ceramics. In practical applications, if the two materials can be jointed, they can make full use of their respective excellent properties to manufacture complex components that meet the requirements, reduce costs, and improve product performance and service life.
However, it is not easy to make jointing between ceramic parts and the metal parts. The chemical bond structure of advanced ceramics and metal materials is different, and the two are almost non-wetting, making good metallurgical jointing difficult; in addition, the thermal expansion coefficients of ceramic parts and metal parts are very different, and the joints are prone to stress when the working temperature changes, and the ceramic side of the joint is prone to Cracking, the phenomenon that the bonding strength of the ceramic and metal connection interface is not high.
Zirconia ceramics is the most suitable ceramic material for connecting with metal among advanced ceramic materials. The elastic modulus and thermal expansion coefficient of zirconia ceramics are close to those of steel, and will not be damaged or burst due to inconsistent thermal expansion. Zirconia ceramics have the advantages of high toughness, high bending strength, high wear resistance, and excellent thermal insulation properties, so they are widely used in the field of structural ceramics.
