Alloy 42 Manufacturer and Supplier

Description:

Alloy 42 is an iron-nickel alloy, consisting of 42% nickel. This controlled expansion alloy has low thermal expansion characteristics over a range of temperatures and has been developed over time with ceramics in mind.

Alloy 42 Properties & Information

Low Thermal Expansion alloys are perfectly suited for use in glass and ceramic seals, providing metallic feed‐throughs from interior to exterior components. Another great use of Alloy 42 is within electrical components. Alloy 42, and similarly Kovar, should always be manufactured according to exact requirements. In ceramics, a low coefficient of thermal expansion (CTE) of must be matched by the feed‐through metal.

Brilliance Special Steel ensures that every alloy is manufactured to provide the ideal coefficient.

Alloy 42 Mechanical Properties

Metallurgical Condition       Annealed, Descaled     

Yield Strength       KSI (MPa)       36 (248)

Tensile Strength    KSI (MPa)       71 (490)

Hardness HB  

Elongation     50mm     >40

Alloy 42 Chemistry

Nickel     Ni    42

Iron Fe    Balance

Alloy 42 Physical Properties

Co Efficient of Thermal Expansion            

30-300°C       10-6/°C  4.0 - 4.7

30-450°C       10-6/°C  6.7 – 7.4

Density   g/cm³     8.15

Curie Temp    °F    626, °C    330

Melting Point °F    2597, °C    1425

Modulus of Elasticity at 20°C       MPa 148

Specific Heat  J/g- °C   0.50

Thermal Conductivity at 20°C     J/cm.s.°C 12.5

Resistivity at 0°C    Μohm.cm      63

Poisson's coefficient           

The History of Alloy 42

Alloy 42 is widely used for military applications. It's hermeticity and attachability to low‐CTE die to low‐CTE lead frames have been cited as 2 main advantages of using Alloy 42. However, when placed into plastic components Alloy 42 has proven to provide disastrous results.

Brilliance Special Steel understands that mismatching can take place with Alloy 42, whether that be a result of surface mount (SM) solder joints connecting materials with different CTEs, or when solder bonds have CTEs that differ from the CTE of solder. We'll work alongside you to ensure that the desired result is found, with little-to-no SM solder joint failures.

Alloy 42 and Kovar not only cause significant global and local thermal expansion mismatches, but are inherently more difficult to solder because of the low solubility of nickel and iron, the main constituents of these alloys. Pull tests of solder joints show that, under the best of circumstances, a solder joint that includes an Alloy 42 or Kovar surface is only half as strong as one made to copper surfaces.