Low Expansion Iron Nickel Alloy 4j36 Alloy Plate 490 - 680MPa Hot Rolled Blackboard Round Rod

Low expansion 4J36 alloy plate hot-rolled blackboard round rod for precision instruments.

4J36 alloy is a special low expansion iron nickel alloy composed of elements such as iron (Fe), nickel (Ni), cobalt (Co), etc. It has unique physical and chemical properties and is widely used in precision manufacturing, electronic packaging, aerospace and other fields.

The main chemical components of 4J36 alloy include iron, nickel, and cobalt, with nickel content typically ranging from 35.0% to 37.0%, iron as the balance, and cobalt content generally not exceeding 0.5%. In addition, it also contains small amounts of elements such as manganese (Mn), chromium (Cr), silicon (Si), carbon (C), phosphorus (P), and sulfur (S). Within the temperature range of -100°C to 200°C, its average coefficient of linear expansion is approximately 1.2 x 10^-6/°C, exhibiting extremely low thermal expansion characteristics.

4J36 alloy has high tensile strength and yield strength, ranging from 490 to 680 MPa and ≥ 240 MPa, respectively. Its elongation rate is between 25% and 35%, and its hardness is 130 to 180 HB in the annealed state, and higher at 170 to 200 HB in the cold-rolled state. These excellent mechanical properties enable 4J36 alloy to withstand significant external forces and deformations, thereby maintaining stable performance in various applications.

The heat treatment process of 4J36 has a significant impact on its performance, mainly including the following steps:

• Homogenization treatment: Heat the alloy to a temperature slightly above its solution line temperature and maintain it for a period of time to ensure uniform distribution of alloy components.
• Rapid cooling: After homogenization treatment, the alloy is rapidly cooled to room temperature or slightly lower to preserve the microstructure of the solid solution.
• Aging treatment: Performed at a lower temperature to adjust the microstructure of the alloy, improving its mechanical properties and stability.
• Annealing treatment (optional): In some cases, annealing treatment may be necessary to further reduce the hardness of the alloy and improve its toughness.

4J36 alloy has demonstrated extensive application value in multiple fields:

• Precision manufacturing: Used for manufacturing precision instruments and meters that require precise dimensions to be maintained under temperature changes.
• Electronic packaging: Commonly used for packaging and connecting electronic components due to its low coefficient of expansion and good weldability.
• Aerospace: Can effectively solve the dimensional stability problem caused by temperature changes in aerospace vehicles.
• Optical instruments: Used to manufacture various key components in optical instruments and precision measuring instruments.

Similar grades of 4J36 include Fe-Ni36 (France), W.Nr.1.3912 (Germany), Ni36 (Germany), X1NiCrMoCu, N 25-20-7 (UK), and UNSK93600 thermostat alloy (USA).

In summary, 4J36, as an expansion alloy with excellent dimensional stability, occupies an important position in the field of materials science. Its unique performance advantages have demonstrated enormous application potential in multiple high-tech fields.