Fixed Expansion Sealing Alloy
Expansion alloys are divided into low expansion alloys and fixed expansion alloys, the latter of which are called fixed sealing alloys.
In addition to having a specific thermal expansion coefficient, expansion alloys are also required to have good sealing, weldability, corrosion resistance, processability and ease of cutting according to different uses, and expansion is not allowed within the use temperature range. Phase transition with obvious changes in characteristics, thereby preventing vacuum leakage and stress in electrical vacuum silicon components;
Fixed expansion alloys have better expansion coefficient management properties and are therefore more commonly used in electric vacuum, semiconductor industries and other special applications.
Products are generally rods, plates, strips, foils, wires and tubes.
Our company mainly provides foil materials in Chinese National Standard GB/T 38940-2020, including 4J330 (4J30), 4J339 (4J35). The ultimate foil specification is 0.02-0.03mm thinnest and the ultimate width is 700mm.
Some other commonly used grades of low expansion alloys as per national standard of GB/T 37797-2019 include 4J329(4J29)/4J336(4J36)/4J342(4J42)/4J343(4J43)/4J335(4J44)/4J347(4J47)/4J350(4J50), etc.
