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. It is mainly used for matching sealing with ceramics and is an important sealing structural material in the electric vacuum industry.

Chemical composition of 4J34 precision alloy

Material

4J34

chemical composition

C

Mn

Si

P

S

Ni

Co

Fe

≦0.05

≦0.5

≦0.3

≦0.02

≦

0.02

28.5-19.5

19.5-20.5

margin

4J34 thermal performance

The thermal properties of 4J34 alloy mainly include its melting temperature and thermal stability.

Melting temperature range: The melting temperature of 4J34 alloy is approximately 1450°C. This means that in high-temperature environments, alloys can begin to melt and lose their structural and performance characteristics. Knowing the melting temperature helps determine the alloy’s maximum operating temperature and usage limitations.

Thermal stability: 4J34 alloy has good thermal stability under high temperature conditions. It maintains its strength, hardness and other mechanical properties in high-temperature environments. This makes the alloy suitable for a variety of high temperature applications such as thermocouples, thermal sensors, etc.

In general, 4J34 alloy has a high melting temperature and good thermal stability, making it of great application value in high temperature environments.

Physical properties of 4J34 precision alloy

Density ρ=8.29g/cm3. ​

Resistivity ρ=0.45μΩ·m.

Curie point Tc=470℃.

Magnetic properties of 4J34 alloy

H/(A/m)

B/T

H/(A/m)

B/T

8

0.7×10-2

160

0.65

16

1.5×10-2

400

1.01

24

2.7×10-2

800

1.21

40

5.6×10-2

2000

1.46

80

0.25

4000

1.62

At 4000A/m, the residual magnetic induction intensity Br=0.89T, and the coercive force Hc=83.2A/m[1,2].

Mechanical properties of 4J34 precision alloy

4J34 tensile strength The tensile strength of wire and strip is as follows:

Status code

Status

σb/MPa

 

wire

Strip

  

R

soft state

<585

<570

Y

Hard state

>860

>700

The tensile properties of 4J34 alloy (annealed state) at room temperature are shown in the table below:

σb/MPa

σP0.2/MPa

δ/%

HV

539

343

32

158

4J34 heat treatment system

The heat treatment system of 4J34 usually follows the following steps:

Prepare performance test specimens specified in standards.

Place the specimen in a protective atmosphere or vacuum to ensure a good heat treatment environment.

Heat the sample to 900℃±20℃ and keep it for 1 hour to allow the sample to reach the required temperature and perform soaking treatment.

Cool the sample slowly, with a cooling rate no greater than 5°C/minute.

When the sample temperature drops below 200°C, take out the sample.

This heat treatment system is designed to ensure that the expansion coefficient and low-temperature structural stability of 4J34 alloy meet standard requirements.

Corrosion resistance of 4J34 precision alloy

4J34 precision alloy has good corrosion resistance in atmosphere, fresh water and sea water environments. This means that it is resistant to common corrosive media, extending its service life and performance stability.

In the atmospheric environment, including common humidity, oxygen and other gas components, 4J34 alloy can better resist oxidation and corrosion. Therefore, it can be used to manufacture parts or equipment that require long-term exposure to the atmosphere.

In fresh water environment, 4J34 alloy also shows high corrosion resistance and has certain corrosion resistance. This makes it suitable for applications such as water treatment and chemical equipment.

In addition, in seawater, 4J34 alloy is widely used in the fields of marine engineering and ocean exploration. Due to its good seawater corrosion resistance, it can resist the erosion of salt and other corrosive substances in seawater, thereby ensuring the stability and reliability of equipment and components in the marine environment.

In summary, 4J34 precision alloy has good corrosion resistance in atmosphere, fresh water and seawater environments, making it an ideal choice for applications with high corrosion resistance requirements in many fields.

Application fields of 4J34

4J34 alloy is mainly used in the following fields:

Electric vacuum components: 4J34 alloy plays a key role in the manufacturing of electric vacuum components. It can be used to manufacture components such as electrodes, lead-out disks and lead-out wires for electron tubes, magnetrons and other components.

Al2O3 ceramic sealing: 4J34 alloy can also be sealed with Al2O3 ceramics. This sealing method is common in electronic device packaging and can effectively protect the electronic components and circuits inside the component.

To sum up, 4J34 alloy is mainly used in the field of electronic component manufacturing, including the manufacturing of electron tubes, magnetrons and other components, and sealing with Al2O3 ceramics.

What should you pay attention to when using 4J34 alloy?

For the use of 4J34 alloy, there are several precautions:

Match with Ceramics: When selecting ceramic materials, make sure that their thermal expansion coefficient matches that of the 4J34 alloy. This can avoid thermal stress and dimensional changes caused by temperature changes and ensure the stability of the connection.

Low-temperature structure stability: When selecting 4J34 alloy, the stability of the low-temperature structure should be checked according to the use temperature. Ensure that the alloy maintains its properties and structural stability at the required temperatures.

Heat treatment: During the processing process, appropriate heat treatment is very important to ensure that the 4J34 alloy has good deep drawing and drawing properties. Appropriate heat treatment process can improve the processability and deformation properties of the alloy.

Air tightness of forged materials: If you choose to use forged materials, check their air tightness strictly. Ensure there are no pores or other defects in the alloy to improve its overall performance and reliability.

To sum up, when using 4J34 alloy, you need to pay attention to the matching with ceramics, low temperature structural stability, heat treatment and the air tightness of the forged material. These considerations can help ensure that the alloy used has good properties and meets the requirements of the specific application