Permalloy 80, a Nickel-Iron-Molybdenum alloy, provides very high initial and maximum magnetic permeabilities and minimal core losses at low field strengths. This vacuum-melted product also offers the advantages of small size and weight in magnetic core and shielding materials for the applications shown below.

Applications:

Permalloy 80 provides high initial and maximum permeabilities with low coercive force, low hysteresis loss, low eddy-current losses, and low magnetostriction. Typical applications for this material are:

• Transformer laminations

• Relays

• Recording Heads

• Deflection and Focusing Yokes

• Amplifiers

• Loudspeakers

• Shielding

MAGNETIC PROPERTIES*

Typical D.C. Magnetic Properties:

              Saturation Flux Density:                       7,500 gausses

              Coercive Force from H = 1 oersted:        0.015 oersted

              Residual Induction:                              3,700 gausses

              Hysteresis Loss from Saturation:            9 ergs/cm³/cycle

              Permeability @ B = 100:                            75,000

              Maximum Permeability:                             300,000

*After appropriate anneal.

Minimum Magnetic Permeabilities:

(B = 40 gauss @ 60 Hz)

                                  Thickness                   μ

                                      .001"                   50,000

                                      .002"                   55,000

                                      .004"                   65,000

                                      .006"                   55,000

                                      .014"                   50,000

All specimens were ring laminations.

 PHYSICAL PROPERTIES:

Density:  g/cm³                8.74

               lb./in³               0.316

Electrical Resistivity:

                microhm-cm        58

                ohm/cer mil-ft     349

Specific Heat:

                 cal/g/^oC            0.12

Thermal Conductivity:

                cal/cm³/sec/^oC    0.047

                BTU/in/ft²/hr/^oF    136

Thermal Expansion

                Coefficient: in/in/^oC

                (-70 to +200 ^oC)     12.0 x 10^-6

Curie Temperature:                  450 ^oC

                                               845 ^oF

TYPICAL CHEMICAL COMPOSITION:

       Nickel                    80%

       Molybdenum           4.4%

       Silicon                   0.3%

       Manganese             0.5%

       Iron                     Balance

TYPICAL MECHANICAL PROPERTIES:

                                                                       Annealed for

                                  Cold                Mill            Magnetic

                                 Rolled         Annealed     Properties

Tensile Strength:            150 ksi          90 ksi         80 ksi

Yield Strength:               135 ksi          35 ksi         30 ksi

% Elongation in 2":             2                40              40

Hardness:                       32R_C            70R_B            55R_B