Expanded Alloy

4J29 alloy is also called Kovar alloy. The alloy has a linear expansion coefficient similar to that of borosilicate hard glass at 20-450°C, a higher Curie point, and good low-temperature structural stability. The oxide film of the alloy is dense and can be well wetted by glass. It does not interact with mercury and is suitable for use in instruments containing mercury discharge. It is the main sealing structural material of electric vacuum devices.

4J33 is a ceramic sealing alloy developed based on my country’s ceramic characteristics. The alloy has a linear expansion coefficient similar to that of 95% Al2O3 ceramics in the temperature range of -60°C to 600°C. It is mainly used for matching sealing with ceramics and is an important sealing structural material in the electric vacuum industry.

4J34 is a ceramic sealing alloy developed based on my country’s ceramic characteristics. The alloy has a linear expansion coefficient similar to that of 95% Al2O3 ceramics in the temperature range of -60°C to 600°C.

4J36 is a special low-expansion iron-nickel alloy with ultra-low expansion coefficient. Among them, the control of carbon and manganese components is very important. Cold deformation can reduce the thermal expansion coefficient, and heat treatment within a specific temperature range can stabilize the thermal expansion coefficient. 4J36 is corrosion resistant in dry air at room temperature. In other harsh environments, such as humid air, corrosion may occur

4J42 alloy is a high-performance metal alloy, mainly composed of iron (Fe) and nickel (Ni). It belongs to the category of precision alloys or fixed expansion alloys. The nickel content of 4J42 alloy is carefully adjusted to obtain specific thermal expansion properties. In addition to iron and nickel, alloys may also contain small amounts of other elements to further improve their properties. Through precise heat treatment and processing technology, 4J42 alloy products with excellent properties can be obtained.

4J50 is a series of constant expansion alloys that can match soft glasses and ceramics with different expansion coefficients within a given temperature range by adjusting the nickel content. Its expansion coefficient and Curie point increase with the increase in nickel content. This combination alloy is a sealing structural material widely used in the electric vacuum industry. 4J50 is a typical grade of glass-sealed alloy. It has been used in aviation factories for a long time and has stable performance.

Iron-nickel fixed expansion alloys are a series of fixed expansion alloys that can match soft glasses and ceramics with different expansion coefficients within a given temperature range by adjusting the nickel content. Their expansion coefficients and Curie points increase with the increase in nickel content. This combination alloy is a sealing structural material widely used in the electric vacuum industry.