INTRODUCTION
4J28 is a kind of Fe-Cr-B glass sealing alloy, which is a duplex structure of Cr24-Fe. It is non-magnetic, has excellent corrosion resistance and is applicable to 300℃, which has excellent corrosion resistance and heat conduction performance. It is suitable for the manufacture of vacuum parts and the sealing of glass joints and some steel parts in chemical instruments.
STRUCTURE AND CHEMICAL COMPOSITION OF 4J28
4J28 is composed of two phases, which is Cr24Fe (gamma phase) and dynamic microstructure (alpha phase). The chemical composition is as follows:
C: 0.01% ~ 0.10%, Si: 0.05% ~ 0.30%, Mn: 0.05% ~ 0.50%, P: ≤ 0.045%, S: ≤ 0.03%, Cr: 23.5% ~ 25.5%, Ni: ≤ 0.50%, Mo: ≤ 0.50%, Co: ≤ 0.35%, Cu: ≤ 0.20%, Al: ≤ 0.20%, V: ≤ 0.30%, W:≤0.10%, Fe: balanced.
PROPERTIES OF 4J28
4J28 makes of high-purity dimetal and has good chemical stability and corrosion resistance. Its physical properties are as follows: density: 8.2g/cm3, long-term continuous use temperature: ≤300℃, expansion coefficient a / 10-6K-1: 11.0, linear expansion coefficient a / 10-6K-1: 12.0, electrical Resistivity Ω cm20℃:3.3.
APPLICATIONS OF 4J28
4J28 has high strength and excellent corrosion resistance, so it is suitable for making vacuum parts, glass joint sealing and some stainless steel parts. It also can be used in chemical instrument, petroleum industry, food industry and other instruments.
ADVANTAGES OF 4J28
1. Good stability under high temperature and high pressure.
2. Excellent thermal conduction performance, excellent anti-corrosion and anti-oxidation.
3.Good wear resistance and good corrosion resistance.
4. Good welding performance and can be widely used in various fields.
5. Low cost, easy processing and long service life.
CONCLUTION
4J28 is a high-quality Fe-Cr-B glass sealing alloy and it has high strength, excellent corrosion resistance, heat conduction performance and other characteristics. It can be used for the manufacturing of vacuum parts, glass joint sealing and some stainless steel parts. It has good adaptability and is widely used in chemical instruments, petroleum industry and food industry. Therefore, 4J28 is a very ideal sealing material.
