Soft Magnetic Alloys . Com
Everything About Soft Magnetic Alloys

Commercial Soft Magnetic Alloys

Soft magnetic materials are those materials that are easily magnetised and demagnetised.

Properties of Soft Magnetic Alloys

The Nominal Composition by Weight %

 Ni Mo Si Mn C Fe
80-81 4.5-6 0.050-0.40 0-0.50 0.010 Bal

Mechanical & Other Typical Properties

Hard Temper Soft Temper Properties of Component after final heat treatment
HV = 125
TS = 550 Mpa
% EL
% EL
325 1000 3 160 700 40
Density Gm / Cms 3 Resistively Curie Temp(OC) Thermal Expansion
8.70 60 400 12

Magnetic Properties After Heat Treatment

Typical Value Some Useful Guaranteed Value
Ui Mm HC
A/c M
50,000 150,000 0.015 0.75 Μ m (dc) – 100,000

Applications of Soft Magnetic Alloys

S. No.   Grade Characteristics Applications
1 Mumetal High permeability, low Magnetic Losses Magnetic Shielding & Magnetic cores
2 Permimphy High permeability-wear resistance & stamp ability Magnetic head cores , High performance Laminations
3 Supermimphy High permeability,High purity improved corrosion resistance Easier to heat treat High sensitivity relay parts for ELCB ,High performance current transformer cores

Applications - General

T.V Shadow Mask


Material – Invar (Ni – 35% Min)


Invar Is Controlled Thermal Expansion Alloys & It Help To Match Holes Of Net Of Shadow Mask For Good Focusing For Clear Picture.




T.V Gun


Invar (Ni 42% Min) Is Used For Control Thermal Expension




LNG Tank


Invar (Ni – 36%Min)


Gas Is Trransported At – 163° C And Closed Atmospheric Pressure And Occuppied 600 Times Less Volume.3


Principle Alloy Characterstic – A Low Mean Co-Efficient Of Thermal Expension Between Ambient Temprature To (-163° C) I.E. Stable Property After Long Expose At Low Tmeprature And Thermal Cycle And Tank Crack And Leakage Of Gas Can Be Controlled. Good Weldability, Bendability And Complete Absence Of Brittleness At Low Temprature.




Lead Frame


Used Ifn Electronic Device As A I/C Support / Silicon Chip


Invar – N42 (Ni – 42%)


It Is Also Based On Expansion Behaviour And Control Thermal Stress




Induction Cooking


Principle – The Maxium Working Tmeprature Is Control By Adopted Ferromagnetic Alloy With Specific Currie Point Set Up Temprature For Cooking – (40-200)° C.




Magnetic Shielding


Soft Magnetic Alloys Are Used Electrical Engineering Industries In Order To Concentrate A Magnetic Flux Lines. As A Consequence, An Effective Conversion Or Magnetic Shielding Can Be Achieved.


Magnetic Alloys (Ni 80% Min) Used For Shielding.






To Detect A Signal For Electrical Safety


Material – Feni80mo5 / Feni50






The Bonding Of Two Material, Who’s Co-Offiecent Of Thermal Expansion Are Controlled And Permit The Controlled Of Deflection






                  Circuit Breaker (Electric Safety)


                  Thermostats (Temprature Limiter):


    • Automotive Industry: Thermal Control Of Water Cooled Engines, Electrical Safety Devices, Controls Panels.


    • Electronic Irons, Aquarium Thermal Control, Boiling Water Machine




                  Time Limiter And Control Devices


    • Cigrettes Lighters, Toasters, Flurescent Lamps Starters, Staircase Lighting Switvhes, Washing Machine Door Control Device






    • Brakes Mechanical Compensation System


    • Diesel Thermal Security Pump Device For Cars And Trucks (T > - 15°C)


    • Drum Brake