• Dali Electronics

SEALING AND EXPANSION ALLOY

Sealing And Expansion Alloy Supplier In India We produce a range of FeNi, FeNiCr and FeNiCo alloys, which are known as controlled expansion alloys. These have a linear coefficient of thermal expansion from close to 0 up to 12 x 10-6/K, within a pre-determined temperature range. These alloys are established as the standard alloys for glass-to-metal and glass-to-ceramic sealing, as well as low expansion alloys.

The thermal expansion coefficients of these alloys can be matched to various types of glass and ceramic.

These alloys can be easily further processed by either hot or cold manufacturing methods. They possess similar machining properties to austenitic steels. Welding and brazing these alloys presents no particular problems.

These are nickel-iron based alloys that are required for applications where a hermetic seal is required between metal and glass or ceramic. They are also used for applications where a certain thermal expansion is required over a given temperature range. Examples of such applications are light bulbs, vacuum tubes, optoelectronics, etc.

Alloy 36 This grade exhibits near zero coefficient of thermal expansion from room temperature to 100 °C. It is used for applications that cannot tolerate any dimensional changes due to temperature changes. It finds use in precision laser measurement equipment, electronic devices, instrumentation, thermostats, and in antenna/aerial technologies. Another common usage is for making the low expansion part of bimetallic thermostats.

Alloy 42 has a constant low rate of thermal expansion up to temperatures approaching 350 °C. The thermal coefficient of expansion of this alloy matches that of soft glass. As a result, it is used for glass-sealing applications in microelectronic components and vacuum devices. Alloy 42 is also used as the core of Dumet wire, which forms the glass-sealing component of the lead-in-wires used in electric light bulbs. This alloy is also used for thermostats and thermo switches.

Alloy 48 has a thermal expansion coefficient which matches that of soda-lime glass. It is widely used for electric wiring in glass-to-metal connections. It is also used in thermostats for industrial applications up to 450 °C.

Alloy 52 is also a glass-to-metal sealing alloy that is used in compact fluorescent lamps (CFL) and other electronic applications.

Alloy 54 is also a glass-to-metal sealing alloy that is used in compact fluorescent lamps (CFLs), special auto lamps, and other electronic applications.

Note : Other variants with customer specified Nickel content can also be manufactured. Please contact us for more details.

ALLOY

AMW-TRADE NAMEALLOYSTANDARDMATERIAL NO. DIN / UNS
Dilation 36FeNi36SEW 385/DIN 177451.3912
Dilation 41FeNi41ASTM F30K 94100
Dilation 42FeNi42SEW 385/DIN 177451.3917
Dilation 46FeNi46SEW 385/DIN 17745 ASTM F301.3920/K 94600
Dilation 51FeNi51SEW 385/DIN 17745 ASTM F302.4478/N 14052
Dilation 51 Cr1FeNi51Cr1SEW 385/DIN 177452.4480
Dilation 29/18FeNi28Co18MnSEW 385/DIN 17745/ASTM F 151.3981/K 94610
Dilation 48Cr6A1FeNi48Cr6A1

AVERAGE CHEMICAL COMPOSITION (mass %)

AMW-TRADE NAMENiCoMnAlCuCrSiFe
Dilation 3636≤ 0.05≤ 0.50≤ 0.10n.sn.s≤ 0.50Bal
Dilation 4141≤ 0.05≤ 0.80≤ 0.10≤ 0.10≤ 0.25≤ 0.30Bal
Dilation 4242≤ 0.05≤ 1.00≤ 0.10≤ 0.15≤ 0.05≤ 0.30Bal
Dilation 4646≤ 0.05≤ 0.80≤ 0.10n.s≤ 0.25≤ 0.30Bal
Dilation 51≥50n.s≤ 0.60≤ 0.10n.s≤ 0.25≤ 0.30Bal
Dilation 51 Cr1≥50≤ 0.50≤ 1.00≤ 0.10n.s0.7-1.1≤ 0.30Bal
Dilation 29/182917.1≤ 0.50≤ 0.10≤ 0.20≤ 0.20≤ 0.20Bal
Dilation 48Cr6A147n.s≤ 0.30≤ 0.40≤ 0.035.3-6.3≤ 0.40Bal

PHYSICAL PROPERTIES

AMW-TRADE NAMEDENSITYMELTING TEMPERATUREELECTRICAL RESISTIVITY AT 20˚CTHERMAL CONDUCTIVITY AT 20˚CMODULUS OF ELASTICITY
g/cm3˚CµΩ mW/m˚kGPa
Dilation 368.214.30.7813137
Dilation 418.214400.6415142
Dilation 428.214400.6215142
Dilation 468.214400.5515152
Dilation 518.314500.4317160
Dilation 51 Cr18.214500.4317157
Dilation 29/188.214500.4517157
Dilation 48Cr6A18.314400.85

THERMAL EXPANSION CHARACTERISTICS

AMW-TRADE NAME AVERAGE LINEAR THERMAL EXPANSION COEFFICIENT 10.6/K, base tempe5rature 20 ˚C, temperatures ˚C INFLECTION-POINT/ CURIE-TEMPERATURE
100 150 200 300 400 500 600
Dilation 36 1.5 1.9 2.6 5.3 8.1 9.9 11.1 230
Dilation 41 4.6 4.4 4.2 4.2 5.8 7.9 9.4 340
Dilation 42 5.8 5.6 5.4 5.4 6.2 355
Dilation 46 7.9 7.8 7.7 7.4 7.3 8.6 9.7 400
Dilation 51 10.3 10.3 10.2 10.1 9.9 10.0 10.9 500
Dilation 51 Cr1 10.4 10.4 10.4 10.4 10.4 10.5 11.0 490
Dilation 29/18 6.5 6.2 5.9 5.4 5.1 6.2 7.8 425
Dilation 48Cr6A1 10.3 340

Heat treatment 900˚C, Medium hydrogen

Annealing time 0.5 h,

Cooling time to 100˚C longer than 10 h

MECHANICAL PROPERTIES

AMW-TRADE NAMEYIELD STRENGTH Rp 0.2TENSILE STRENGTH RmELONGATIONBRINELL-HARDNESS
MPaMPa%HB
Dilation 3628050035130
Dilation 4127050035130
Dilation 4230051030130
Dilation 4637050035140
Dilation 5128055030135
Dilation 51 Cr128056030135
Dilation 29/1835054035155
Dilation 48Cr6A154030130

Average values for condition “Annealed and recrystallized”

DIMENSIONS AND TOLERANCES

THICKNESS TOLERANCES

THICKNESSWIDTH 10 -50WIDTH > 50 – 200WIDTH > 200 – 320
0.10 – 0.20+ 0.010± 0.015± 0.020
> 0.20 – 0.50+ 0.020± 0.020± 0.030
> 0.50 – 1.00+ 0.030± 0.030± 0.040
> 1.00+ 0.050± 0.050± 0.070

Other thickness and tolerances on request.

WIDTH TOLERANCES

WIDTHTHICKNESS 0.10 – 0.20THICKNESS > 0.20 – 0.50THICKNESS > 0.50 – 1.00THICKNESS > 1.00 – 2.00THICKNESS > 2.00
10 – 50 ± 0.1± 0.2± 0.2± 0.3± 0.4
> 50 – 200 ± 0.2± 0.3± 0.3± 0.4± 0.5
> 200 – 320 ± 0.3± 0.4± 0.5± 0.6± 0.8

Other thickness and tolerances on request.

LENGTH TOLERANCES (CUT LENGTH)

THICKNESSLENGTH 500 – 3000
0.40 – 2.00+ 10

Other tolerances on request.

PRODUCT FORM (mm)

FORMTHICKNESSWIDTHLENGTHCOIL-IDCOIL-OD
Strips0.10 – 3.0010 – 320300 / 400 / 500Max. 1050
Cut Length0.40 – 2.0050 – 320500 – 300