Nickel Iron Alloy 42/ Nilo 42 (ASTM F30)

Technical Data Sheet

Chemical Composition Limits
Weight% Ni C Mn P S Si Cr Al Fe
Alloy 42
Nilo 42
41 min 0.05 max 0.80 max 0.025 max 0.025 max 0.030 max 0.250 max 0.10 max Rem

Alloy 42 (Nilo 42) is a nickel-iron controlled-expansion alloy containing 42% nickel. Alloy 42 (Nilo 42) has a low and normally constant coefficient of thermal expansion from room temperature to about 300ºC (570ºF). Alloy 42 (Nilo 42) is used for semiconductor lead frames in integrated circuits, bi-metal thermostat strip, thermostat rods, for ceramic-to-metal seals with alumina ceramics, and various glass-to-metal seals such as the core of copper-clad-wire for sealing into glass envelopes of electric bulbs, radio valves, television tubes and fluorescent lights.

Typical Mechanical Properties

Material Condition Tensile Strength Yield Strength (0.2% Offset) Elongation (%)
psi MPa psi MPa
Alloy 42 (Nilo 42) Annealed 71,000 490 36,000 250 43

Alloy 42 (Nilo 42) is available in Sheet, Bar, Plate and Wire. For all stock availability contact Sales.

Stock Sizes
TK X Width X Length
Coil Sheet Foto Etching & Chemical Milling Quality Coil Lead Frame or Deep Draw Hot Rolled Plate
TK X Width X Length
0.005 x 16 yes yes yes yes 0.250+ x WI x
0.375+ x WI x
0.625 + xWI x

Master Plates cut to size
Flame Cutting
0.006 x 16 yes yes yes yes
0.0075 x 16 yes yes yes yes
0.008 x 16 yes yes yes yes
0.010 x 16 yes yes yes yes
0.015 x 16 yes yes yes yes
0.020 x 24 x 72 yes yes yes yes
0.030 x 24 x 72 yes yes yes yes
0.040 x 24 x 72 yes yes   yes
0.061 x 24 x 72 yes yes   yes
0.080 x 10 yes     yes
0.100 x 24 x 72   yes    
0.125 x 16 x 72   yes    

Many other sizes and forms available Alloy 42 Bar, Alloy 42 Plate, Alloy 42 Sheet, Alloy 42 Strip, Alloy 42 Wire

UNS: K94100
Werkstoff Nr. 1.3917
ASTM F29 Wire
ASTM F30 Sheet, Strip, Rod, Bar, Tubing, Wire
B753 Sheet and Strip
SEW 385 Sheet, Strip, Bar
DIN 17745
AFNOR NF A54-301
Tradename Nilo 42

At Aircraft Materials we specialise in the rapid turn-around of orders, with most stock items ready for shipping out the same day to anywhere in the world. For time-critical orders, such as AOGs use our AOG service desk (, the team are dedicated to processing and dispatching orders on the same day, even for cutting orders on bar and sheet products.

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Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.