4j29 Imported Precision Alloy High Magnetic Permeability Iron-Nickel Alloy Kovar Material Properties

• Product Type: Rod
• Material: FeSi
• Carbon Content: Low Carbon
• PCD: 100mm
• ET: 15mm
• Hole: 0
• Model NO.: 4J29
• Delivery: 7-15 Days
• Price Item: T/T,30% Payment in Advance,70% T/T After The Cop
• Quality Control: Mill Test Certificate Is Supplied with Shipment
• Export Country: USA,Southeast Asia,MID East,Africa,Eastern Asia,
• Transport Package: Waterproof Cloth Packaging and on Pallets, or AC
• Specification: 2.0*1250*C/1.5*1250*C/0.8*1250*C/1.0*1250*C
• Trademark: China
• Origin: China

Product Description

4J29
4J29 alloy is also called Kovar alloy. The alloy has a linear expansion coefficient similar to that of borosilicate hard glass at 20-450°C, a higher Curie point, and good low-temperature structural stability. The oxide film of the alloy is dense and can be well wetted by glass.  It is the main sealing structure material of electric vacuum devices

Application overview and special requirements
 The alloy is a typical Fe-Ni-Co hard glass sealing alloy used internationally. It has been used by aviation factories for a long time and has stable performance. It is mainly used for glass sealing of electric vacuum components such as launch tubes, oscillating tubes, ignition tubes, magnetrons, transistors, sealing plugs, relays, lead-out wires of integrated circuits, chassis, shells, brackets, etc. In the application, the selected glass should match the expansion coefficient of the alloy. Its low-temperature tissue stability is strictly tested according to the use temperature. Appropriate heat treatment should be carried out during processing to ensure that the material has good deep drawing and drawing properties. When using forgings, their airtightness should be strictly checked.

Alloy structure
After the alloy is treated according to the heat treatment system specified in 1.5, it is then frozen at -78.5°C, and martensite should not appear for 4 hours or more. However, when the alloy composition is inappropriate, different degrees of austenite (γ) to acicular martensite (α) transformation will occur at room temperature or low temperature, and the phase transformation is accompanied by volume expansion effect. The expansion coefficient of the alloy increases accordingly, resulting in a sharp increase in the internal stress of the seal, and even causing partial damage. The main factor affecting the microstructure stability of the alloy at low temperature is the chemical composition of the alloy. It can be seen from the Fe-Ni-Co ternary phase diagram that nickel is the main element to stabilize the γ phase, and a high nickel content is conducive to the stability of the γ phase. As the total deformation rate of the alloy increases, its microstructure tends to be more stable. Alloy composition segregation may also cause γ→α phase transformation in local areas. In addition, coarse grains will also promote the γ→α phase transformation.

Chemical composition

C	Mn	Si	P	S	Cu	Cr	Mo	Ni	Co	Fe
								28.5	16.8
0.03	0.5	0.30	0.020	0.020	0.20	0.20	0.20	29.5	17.8	allowance

Under the condition of average linear expansion coefficient reach standard, allow the content of nickel and cobalt deviate from the prescribed scope. Aluminum, magnesium, zirconium and titanium content is more than 0.10%, the total amount should be no greater than 0.20%.

 

Solucky steel Limited is a third-party supply chain service enterprise focusing on materials for automobiles, high-end household appliances, as well as material processing and storage. Its headquarters and warehouse base are set up in Shanghai BaoShan, and has branches all over the country, 20+ subsidiary companies,including Foshan, Guangdong, Chongqing, Wuxi, etcz.

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Why Choose Us

FAQ
1.Where is your factory?
Our head office and warehouse located in Shanghai--the biggest steel making center of China

2.How long is your delivery time?
Generally it is 5-10 days if the goods are in stock. or it is 15-30 days if the goods are not in stock, it is according to quantity.

3.What about the MOQ?
MOQ only 200KG,include coils and sheets

4. How long is your lead time?
In general, our delivery time is within 7-15 days, and may be longer if the quantity is extremely large or special circumstances occur.

5.How's your product quality?
We only sell mid to high end steel materials,100% quality guarantee and cost-effective.
6.What are your terms of payment?
You can make the payment to our bank account,T/T, 30% deposit in advance, 70% balance against the copy of B/L.

7.How many countries you already exported to?
We have exported to America, Canada, Brazil, Chile, Colombia, Russia, Ukraine, Thailand, Myanmar, Vietnam, India, Kenya, Ghana,somalia and other African countries.Our export experience is rich, we familiar with different market demands, can help customers avoid a lot of trouble.

8.What are the certifications for your products?
We have ISO 9001, MTC, third parties' inspections are all available such SGS, BV ect.