1.3917, AISI Ni42

 1.3917, AISI Ni42

Designation by Standards

 

Chemical Composition (in weight %)

Description
This alloy is a 42% nickel-iron controlled expansion alloy which has been used in a wide variety of glass-to-metal sealing applications. While the expansion properties of this alloy most closely match 1075 glass, it has also been used in seals fo the 0120 and 0010 glasses. It may also be used with hard glasses if a thin edged tubular seal is used. For seals that are not hydrogen annealed prior to sealing, a variation of this alloy containing small additions fo titanium, Glass Sealing 42 Gas-Free, has been used to promote gas-free sealing characteristics.

Applications
Commonly employed in electronic equipment such as radios, laser systems and thermostats. Alloy has been used for the glass-to-metal seals in electronic tubes, automotive and industrial lamps, transformer and capacitor bushings and other glass-to-metal and ceramic-to-metal applications.

Physical properties (avarage values) at ambient temperature
Modulus of elasticity [10³ x N/mm²]: 215
Density [g/cm³]: 8.12
Thermal conductivity [W/m.K]: 74.0
Electric resistivity [Ohm mm²/m]: 0.66
Specific heat capacity[J/g.K]: 0.50
Curie Temperature: 380^oC

Coefficient of Linear Thermal Expansion 10^{-6 o}C^-1

Soft Annealing
Heat to 788^oC and hold at heat for at least one-half hour per inch of thickness, air cool.

Hardening
This alloy will not respond to hardening by thermal treatment.

Forging
Hot forming temperature: The forging temperature should be 1177-1204^oC. Avoid prolonged soaking to prevent sulfur absorption from the furnace atmosphere.

Machinability
The alloy is readily machinable by conventional techniques.

Corrosion Resistance
This alloy has good resistance to corrosion by mild atmospheres, fresh and salt water.

Cold working
The alloy has good ductility and is readily cold worked.

Welding
Any of the conventional welding methods can be used. When filler rod is required, Glass Sealing 42 is suggested.