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4j29 Strip 0.2mm*95mm Precision Expansion Alloy Iron-Nickel Alloy Permalloy Coil / Foil

4j29 Strip 0.2mm*95mm Precision Expansion Alloy Iron-Nickel Alloy Permalloy Coil / Foil

Package size per unit product 50.00cm * 50.00cm * 30.00cm Gross weight per unit product 55.000kg 4J29 strip 0.2mm*95mm P;
Basic Info
Model NO. 4J29
PCD No
ET No
Hole No
Certificate SGS, ISO, RoHS
Sample Free Sample
Resistivity(μΩ.M) 0.48
Density, g/cm3 8.2
Surface Treatment Bright or Oxidation
Width 9~250 mm
Application Sealing Material
Elastic Modulus, E/ Gpa 138
Temperature Factor of Resistivity 3.7~3.9
Curie Point Tc/ ºC 430
Transport Package Coil+ Waterproof Paper+ Wooden Case
Specification Thickness: 0.1~5.0 mm
Trademark Ohmalloy
Origin Shanghai, China
HS Code 7226999001
Production Capacity 35000 Kgs Per Month
Packaging & Delivery
Package size per unit product 50.00cm * 50.00cm * 30.00cm Gross weight per unit product 55.000kg
Product Description
4J29 strip 0.2mm*95mm Precision expansion alloy Iron-Nickel Alloy permalloy coil / foil
OHMALLOY
OhmAlloy-4J29 (Expansion alloy)
(Common Name: Kovar, Nilo K, KV-1, Dilver Po, Vacon 12)OhmAlloy-4J29 also known as Kovar 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. Most metals cannot seal to glass because their coefficient of thermal expansion is not the same as glass, so as the joint cools after fabrication the stresses due to the differential expansion rates of the glass and metal cause the joint to crack.

OhmAlloy-4J29was 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. Most metals cannot seal to glass because their coefficient of thermal expansion is not the same as glass, so as the joint cools after fabrication the stresses due to the differential expansion rates of the glass and metal cause the joint to crack.

OhmAlloy-4J29 not only has thermal expansion similar to glass, but its nonlinear thermal expansion curve can often be made to match a glass, thus allowing the joint to tolerate a wide temperature range. Chemically, it bonds to glass via the intermediate oxide layer of nickel oxide and cobalt oxide; the proportion of iron oxide is low due to its reduction with cobalt. The bond strength is highly dependent on the oxide layer thickness and character. The presence of cobalt makes the oxide layer easier to melt and dissolve in the molten glass. A grey, grey-blue or grey-brown color indicates a good seal. A metallic color indicates lack of oxide, while black color indicates overly oxidized metal, in both cases leading to a weak joint.

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.

Normal composition%
Ni28.5~29.5FeBal.Co16.8~17.8Si≤0.3
Mo≤0.2Cu≤0.2Cr≤0.2Mn≤0.5
C≤0.03P≤0.02S≤0.02

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(Om*mm2/m)0.48
Temperature factor of resistivity(20ºC~100ºC)X10-5/ºC3.7~3.9
Curie point Tc/ ºC430
Elastic Modulus, E/ Gpa138

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
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 time 14 min~1h.
Cooling rateNo more than 10 ºC/min cooled to 200 ºC

Style of supply
Alloys NameTypeDimension
OhmAlloy-4J29WireD= 0.1~8mm
OhmAlloy-4J29StripW= 5~250mmT= 0.1mm
OhmAlloy-4J29FoilW= 10~100mmT= 0.01~0.1
OhmAlloy-4J29BarDia= 8~100mmL= 50~1000

FAQ

1. What's the minimum quantity customer can order?
If we have your size in stock, we can provide any quantity you want.
If we do not have, for spool wire, we can produce 1 spool, about 2-3kg. For coil wire, 25kg.
2. How can you pay for small sample amount?
We have Western union account, wire transfer for sample amount also ok.

3. Customer do not have express account. How will us arrange the delivery for sample order?
Just need to provide your address information, we will check the express cost, you can arrange the express cost together with sample value.

4. What's our payment terms?
We can accept LC T/T payment terms, it also depending on delivery and total amount. Let's talk more in details after getting your detailed requirements.

5. Do you provide free samples?
If you want several meters and we have stock of your size, we can provide, customer need to bear the International express cost.

6. What's our working time?
We will give you reply through email/phone Online contact tool within 24 hours. No matter working day or holidays.
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