Glass sealing alloy kovar metal 4J29 price

Glass sealing alloy kovar metal 4J29 price

Short Description:

4J29 is also known as Kovar alloy; because of its similar expansion coefficient to glass, it is often called glass sealing alloy in production and processing. After long-term use in aviation factories, the performance is stable. It is mainly used for the glass sealing of electric vacuuglass sealingm components and launch tubes, oscillation tubes, ignition tubes, magnetrons, transistors, sealing plugs, relays, integrated circuits, chassis, housing brackets, etc.The main supply form of the product:wire,strip,plate,bar,pipe.The minimum order quantity is 50kg.


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4J29 is also known as Kovar alloy; it has a linear expansion coefficient similar to that of silicon boron hard glass at 20 to 450°C, so it is often called a glass seal alloy in production and processing. This alloy is a typical Fe-Ni-Co hard glass sealing alloy used internationally, with a high Curie point and good low-temperature microstructure stability. The alloy's oxide film is dense, can be well infiltrated by glass, and does not interact with mercury. It is suitable for use in mercury-containing discharge meters. It is the main sealing structure material for electric vacuum devices. It is mainly used for electric vacuum components and emission tubes. Glass sealing of oscillating tube, ignition tube, magnetron, transistor, sealing plug, relay, integrated circuit lead wire, chassis, housing bracket, etc. In the application, it should be ensured that the selected glass matches the expansion coefficient of the alloy, and its low-temperature structural stability can be strictly checked according to the temperature of use. Appropriate heat treatment should be carried out during processing to ensure that the material has good deep drawing elongation. The alloy is heated to 900°C±20°C in a hydrogen atmosphere for 1 hour, then heated to 1100°C±20°C, held for 15 minutes, and cooled to below 200°C at a rate of no more than 5°C/min.When forging materials are used, their air tightness should be strictly inspected.

Chemical composition(%)
























Tensile strength, MPa

Status number









1/4 Hard




1/2 Hard




3/4 Hard







Physical properties

Density Resistivity
at 20℃ 
Temperature coefficient of resistance (20℃~100℃) Elastic modulus Curie point
(g/cm3)  (Ωmm2/m) X10-5/℃  E/ Gpa Tc/ ℃
8.2 0.48 3.7~3.9 138 430

Coefficient of expansion 





























Thermal conductivity

θ/℃ 100 200 300 400 500
λ/ W/(m*℃) 20.6 21.5 22.7 23.7 25.4


Product heat treatment process
Stress relief annealing Heat to 470~540℃, keep warm for 1~2 h. Cool in the furnace.
Annealing Heating to 750~900℃ in vacuum
Holding time  14 min~1h.
Cooling method Cool down to 200 ℃ at a rate not exceeding 10 ℃/min

Supply form and specification

Alloy grade Type Size
4J29 Wire D= 0.1~8mm
4J29 Strip W= 5~250mm T= 0.1mm
4J29 Foil W= 10~100mm T= 0.01~0.1
4J29 Bar Dia= 8~100mm L= 50~1000

Expansion alloy Series:

4J29   4J33   4J36   4J42

Company Profile

Shijiazhuang Chengyuan Alloy Material Co., Ltd. is a high-tech enterprise specializing in the production of various alloy materials. It has an advanced and complete production line, including material smelting, surface cleaning, rolling, slitting, and a complete test process. Meet the corresponding quality inspection of different products. The company focuses on the production and supply of various electric heating alloys, expansion alloys, soft magnetic alloys, elastic alloys, high temperature alloys and all kinds of pure metals. The product forms include wire, flat wire, strip, plate, bar, foil, Seamless pipe, wire mesh, powder, etc. can meet the application needs of different customers. The various performance indicators of the product are strictly in accordance with the national standards. If customers put forward non-standard requirements, they can also be implemented by reference.


Our products are widely used in heating equipment, machinery manufacturing, electric furnace production, instrumentation, household appliances, mineral mining, aerospace, petroleum and nuclear power and other industries, and have received good market feedback. Our products have stable delivery time, excellent quality, sophisticated packaging, and high repurchase rate. They are not only widely recognized in the domestic market, but also have a good reputation in the international market.


Packing and transport

Application area

Application area

Our service

* OEM manufacturer

* We will deliver the goods to the warehouse of the customer's agent in any city in China.

* Terms of delivery: EXW, FCA, FOB, CIF, CPT, DAP

* Mode of transport: Sea, Auto, Railway, Air and Express

* Payment terms: Bank Transfer, Western Union, PayPal, Alipay

* Quality Certificate:

In order to improve the quality of products and services, with each order we provide a quality certificate for goods, which includes measured data - chemical composition, electrical resistivity, tensile strength, elongation, melting number, etc.

Cheng Yuan Alloy Material Co., Ltd

Email: alexey@chyalloy.com

Tel .: +86 13673186216

+86 311 8803 3197




Q: Does your company provide samples?

A: Yes, we provide samples for free, and buyers need to bear the corresponding shipping costs.

Q: How long is your company's delivery time?

A: If the goods are in stock, it is usually 5-10 days. Or if the goods are not in stock, it is 15-20 days, according to quantity.

Q: What are the payment terms of your company?

A: Payment <=1000USD, 100% in advance. For payment>=1000 USD, pay 30% T/T in advance, and pay the balance before shipment.

Q: Do you test all goods before delivery?

A: Yes, we have a strict product inspection process, and 100% testing will be carried out before delivery.

Q: How does your company maintain long-term and stable business relationships with customers?

A: 1. We strictly control the quality of our products and the prices are reasonable to ensure that our customers benefit;

2.We do our best to do a good job in product packaging to ensure that the product is intact during transportation.

3.In order to meet the requirements of customers in different countries for product performance, we have a separate test furnace to debug product performance.

Q: How to get in touch with your company?

A: You can contact us at any time via email, phone, fax, Skype, Whatsapp or mobile phone,

Phone/Whatsapp/WeChat: +86-13673186216

Email: alexey@chyalloy.com

Q: What are your working hours?

A: Monday to Sunday: 24 hours, any time, as long as you need it, you can contact us. We will reply to you as soon as possible.

Q: What are the payment terms of your company?

A: T/T, L/C, D/A, D/P, Western Union, MoneyGram, Paypal.

Ready to get started? Contact us today for a free quote!

Aestu onus nova qui pace! Inposuit triones ipsa duas regna praeter zephyro inminet ubi.

Ready to get started? Contact us today for a free quote!

Aestu onus nova qui pace! Inposuit triones ipsa duas regna praeter zephyro inminet ubi.

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    Large size range from 0.025mm (.001”) to 21mm (0.827”)

    Order Quantity ranging from 1 kg to 10 tonnes
    At Cheng Yuan Alloy, we take great pride in customer satisfaction and frequently discuss individual requirements, offering a tailored solution through manufacturing flexibility and technical knowledge.

    Delivery within 3 weeks
    We typically manufacture your order and ship within 3 weeks, delivering our products to more than 55 countries across the world.

    Our lead times are short because we stock in excess of 200 tonnes of more than 60 ‘High Performance’ alloys and, if your finished product is not available from stock, we can manufacture within 3 weeks to your specification.

    We take pride in our more than 95% on time delivery performance, as we are always striving for excellent customer satisfaction.

    All wire, bars, strip, sheet or wire mesh are securely packed suitable for transporting by road, air courier or sea, with available in coils, spools and cut lengths. All items are clearly labelled with the order number, alloy, dimensions, weight, cast number and date.
    There is also the option to supply neutral packaging or labelling featuring the customer’s branding and company logo.

    Order is manufactured to your specification
    We produce wire, bar, flat wire, strip, sheet to your exact specification and in exactly the quantity you are looking for.
    With a range of 50 Exotic Alloys available, we can provide the ideal alloy wire with specialist properties best suited to your chosen application.
    Our alloy products, such as the corrosion resistant Inconel® 625 Alloy, is designed for aqueous and off-shore environments, while the Inconel® 718 alloy offers superior mechanical properties in low and sub-zero temperature environments. We also have high strength, hot cutting wire ideal for high temperatures and perfect for cutting polystyrene (EPS) and heat sealing (PP) food bags.
    Our knowledge of the industry sectors and state-of-the-art machinery means we can reliably manufacture alloys to strict design specifications and requirements from all over the world.

    Our ‘Emergency Manufacturing Service’ for delivery within days
    Our usual delivery times are 3 weeks, however if an urgent order is required, our Emergency Manufacturing Service ensures your order is manufactured within days and shipped to your door via the fastest route possible.

    If you have an emergency situation and require products even faster, contact us with your order specification. Our technical and production teams will swiftly respond to your quote.

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