4J78 Precision Alloy Non-Magnetic Fixed Expansion Ceramic Seal Alloy

Lork Group is a super alloy manufacturer with 20 years of manufacturing experience. Engaged in offering best in class alloy products that can be accessible in varied specifications as per the industry requirement. 4J78 Variety Specifications and Supply Status Varieties include rods, tubes, plates, wires and strips.

 

4J78 alloy has low magnetic permeability and lower expansion coefficient compared with other non-magnetic ceramic seal alloys, so it is called non-magnetic fixed expansion ceramic seal alloy. Adding a small amount of copper to the alloy can improve its processing performance. The overall performance of the alloy's ceramic seal is superior to that of non-magnetic ceramic seal materials such as Monel, stainless steel, and oxygen-free copper.

 

4J78 alloy is mainly used as non-magnetic ceramic sealing material in electric vacuum devices.

4J78 alloy is used as a non-magnetic ceramic sealing material for gyroscopes and other electric vacuum devices. In use, the heat treatment process should be strictly controlled to ensure that the alloy has good processing properties.

Under the condition that the average linear expansion coefficient reaches the standard, the content of molybdenum and copper is allowed to deviate from the range specified in the table.

 

The melting temperature range of 4J78 alloy is 1400~1420ºC. 4J78 Melting and Casting Process Vacuum induction furnace is used for melting.

 

4J78 Alloy heat treatment system The expansion coefficient performance test sample specified in the standard is heated to 1000-1050°C in a protective atmosphere or vacuum, kept for 30-40 minutes, cooled to below 300°C at a speed of no more than 5°C/min, and released from the furnace.