Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process
HomeHome > Products > UNS Alloy Pipe > Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process
Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process

Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process

Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process General Description Kovar is a nomin
Basic Info.
Model NO. Kovar, Kovar
Length 0.5-3000mm
Surface Bright
ASTM F30
Standsrd GB/DIN/JIN/ASTM
sample accepted small order
OD 0.5-20mm
WT 0.02mm Min.
Type Seamless
Transport Package Wooden Case
Specification OD: 0.5-20mm
Trademark TANKII
Origin Shanghai, China
HS Code 75071200
Production Capacity 20 Ton/Month
Product Description
Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process

Controlled Expansion and Glass Sealing Alloys
German standard number Tradename DIN UNS
1.3912Alloy 3617745K93600/93601
1.3917 Alloy 42 17745K94100
1.3922 Alloy 4817745 K94800
1.3981Pernifer2918 17745 K94610
2.4478 NiFe 4717745 N14052
2.4486 NiFe47Cr17745-

General Description
Kovar is a nominal 29%Ni-17%Co-54%Fe alloy that is a well-known glass-sealing alloy suitable for sealing to hard glasses. Kovar has a nominal expansion coefficient of approximately 5 ppm/°C and inflection temperature of ~450 °C (840 °F).
4J29 also known as Fe-Ni-Co Glass Sealing Alloy. it was invented to meet the need for a reliable glass-to-metal seal, which is required in electronic devices such as light bulbs, vacuum tubes, cathode ray tubes, and in vacuum systems in chemistry and other scientific research.
Kovar (ASTM F15) has been used for making hermetic seals with the harder Pyrex glasses and ceramic materials. This alloy has found wide application in power tubes, microwave tubes, transistors, and diodes. In integrated circuits, it has been used for the flat pack and the dual-in-line package.

Mainly used in electric vacuum components and emission control, shock tube, igniting tube, glass magnetron, transistors, seal plug, relay, integrated circuits lead, chassis, brackets and other housing sealing.

Chemical Domposition

alloyCMnSiPSNiCrCoCuMoFe
4J29≤0.03≤0.50≤0.30≤0.020≤0.02028.5~29.5≤0.2016.8~17.8≤0.2≤0.2balance

Tensile Strength, MPa

Code of conditionConditionWireStrip
RSoft≤585≤570
1/4I1/4 Hard585~725520~630
1/2I1/2 Hard655~795590~700
3/4I3/4 Hard725~860600~770
IHard≥850≥700

Typical Physical properties

Density (g/cm3)8.2
Electrical resistivity at 20ºC(OMmm2/m)0.48
Temperature factor of resistivity(20ºC~100ºC)X10-5/ºC3.7~3.9
Curie point Tc/ ºC430
Elastic Modulus, E/ Gpa138

The heat treatment process
Annealing for stress reliefHeated to 470~540ºC and hold 1~2 h. Cold down
annealingIn vacuum heated to 750~900ºC
Holding time14 min~1h.
Cooling rateNo more than 10 ºC/min cooled to 200 ºC

Coefficient of expansion

θ/ºCα1/10-6ºC-1θ/ºCα1/10-6ºC-1
20~607.820~5006.2
20~1006.420~5507.1
20~2005.920~6007.8
20~3005.320~7009.2
20~4005.120~80010.2
20~4505.320~90011.4

Thermal conductivity

θ/ºC100200300400500
λ/ W/(m*ºC)20.621.522.723.725.4

Style of supply

Alloys NameTypeDimension
4J29WireD= 0.1~8mm
4J29StripW= 5~250mmT= 0.1mm
4J29FoilW= 10~100mmT= 0.01~0.1mm
4J29BarDia= 8~100mm

L= 50~1000mm

Expansion Alloy 29HK Kovar Uns K94610 Tube Ni29co18 FeNi29 pipe for Sealing Process