Xi'an Gangyan specilalized in manufacturing high-quality percision alloy for 23+ years.
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Location:No. 88 East of Century Avenue, XianYang, Shaanxi, China. P.C. 712046

Alloy 426

Sealmet HC-4, alloy 426, ASTM F31, UNS k94760, (Fe-42Ni-6Cr), Chinese 4J6
A controlled expansion alloy, consisting of 42% Nickel, 6% Chromium, balance Iron; used in a wide variety of electronic applications, especially for glass seals.
Forms: Sheet/Plate, Bar/Rod/Wire/Coil,Capillary/Pipe/Tube
Order Email:sales@xagy.cn


A nickel-chromium-iron which has been developed to match the thermal expansion characteristics of 0120 glass. An additional advantage of this alloy for glass-to-metals seals is the tight dark green oxide coating formed by wet hydrogen annealing at 1900/2200°F (1038/1204°C) for one hour. The oxide tends to flux with the glass and make it a vacuum tight seal if the surfaces are clean. To obtain the necessary surface cleanliness, pickle in muriatic acid.


Glass to metal seals for a variety of electronic tubes and CRT tubes. It is supplied in wire form for compression seals.


Cross Reference:

Russia USA Japan France Germany
H42 X 6 42Ni-6Cr Carpenter426 Sylvania4 Sealmet4 NRS-1 YEF-426 SNC ASV(426) Ni42Cr6 Vacovit426 (NiCr426

Typical chemistry:

C P S Mn Si Al Ni Cr Fe
0.05 0.020 0.020 0.25 0.30 0.20 41.5-42.5 5.5-6.3 balance

Physical property:

Density :0.29  lb/in³,  8.2 g/cm3 Melting Range: 2600°F (1430°C)

Average Coefficient of Linear Expansion:

Heat Treatment of the Samples Mean Coefficient of Linear Expansion
20 to 300℃ 20 to 400℃
To be heat treated at a temperature of 1130±20℃ the hydrogen, hold for 15 min., cool to 200℃ at a rate less than 5℃/min 7.6-8.3 9.5-10.2

Mean Coefficient of Thermal Expansion

20-100℃ 20-200℃ 20-300℃ 20-400℃ 20-500℃ 20-600℃
6.8 7.0 7.7 9.7 11.1 12.2

The mechanical property of Alloy 42-6:

Tensile Strength 80KSI 552MPA
Yield Strength 40KSI 276MPA
Elongation 30%
Hardness Rb 71

Size Range

Sheet Thickness:0.10mm~3.50mm, width: ≤300mm
Plate Thickness:3.5mm~40.0mm, width: ≤500mm
Round wire Thickness:0.10mm~5.0mm
Flat Wire Dia 0.5mm~Dia 5.0mm, length≤1000
Rod Dia 5.0mm~Dia 8.0mm, length≤2000
Dia 8.0mm~Dia 32.0mm, length≤2500
Dia 32.0mm~Dia180.0mm, length≤1000
Capillary OD 8.0mm~1.0mm,ID 0.1~8.0 length≤2500
Pipe OD 120mm~8.0mm,ID 8.0~129 length≤4000

Condition: (With max tolerance) cold rolled, cold drawn, hot rolled , hot forging ,peeled turned ,bright ,bright annealed

XAGY Advantages

1. High-qulity product

  • ISO9001:2008 International Quality System Certification.
  • With advanced equipments: VIMF, Induction Furnace, ESR Furnace ect.
  • Strict Quality-testing System.

2. Strong R & D Strength

  • 40,000㎡ production base.
  • 60+ R & D team members, with rich customization experience.
  • A good assortment of alloy to choose.

3. Efficient delivery

  • Flexible transport means, very convenient.
  • Tailor a suitable transport plan.

4. Good service

  • We provide online service, information feedback within 24 hours.
  • Professional team to provide remote technical advice and guidance.

Contact XAGY

Xi'an Gangyan Special Alloy Co., Ltd.

Hotline: 0086-29-33669103

Fax: 0086-29-33698670

Email: sales@xagy.cn

Add.: No. 88 East of Century Avenue, XianYang, Shaanxi, China. P.C.712046

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