MAXIMAG® is a high purity soft iron suitable for the manufacture of frames, yokes, armatures, cores etc in telephone relays, solenoids, magnetic clutches, magnetic brakes and all stationary parts of magnetic circuits carrying a direct flux.

Many other applications in the electrical and electronic equipment industry.

Also used for Sacrificial Anodes, for example in the protection of condensers and pumps for the electricity generation and shipping industries and in water de-salination plants.

Whilst strategic stock sizes are held, semi finished material is always available to enable further processing to satisfy individual customer requirements.

MAXIMAG® is sometimes referred to as Swedish Iron, Pure Iron, Soft iron and Magnetic Iron.

Chemical Properties

The specification quoted below can be maintained consistently from cast to cast. Specific analysis for 13 elements is provided for every cast. Material made to this composition, with the following heat treatment, provides typical electromagnetic properties as per the table below. Mechanical properties can be independently tested on request at additional cost.

Maximag® CSiMnSP
max <0.02% max 0.05% max 0.20% max 0.02% max 0.01%

Heat Treatment

The heat treatment required to produce these typical electromagnetic properties, consists of full annealing from 920ºC (ie 920º C soak, furnace cool at 50º C/hour max to 600º C, furnace cool to room temperature).

In order to avoid scaling, this treatment should be carried out in a neutral or slightly reducing atmosphere. Typical hardness after annealing 95-110 B.H.N. Annealing is normally done after any significant machining work, but can be arranged on request.

Electromagnetic Properties

Normally conforming to MoD specifications DTD 5092 and DTD 5102, which although obsolete, are commonly used as a basis for the typical electromagnetic properties which are expected to be achieved following the annealing process.

In order to develop the optimum electromagnetic properties, the material must be subjected to the above annealing treatment, preferably after rough machining. Toroidal ring testing is expected to yield results exceeding the minima quoted below:

H (oersteds)
M.K.S. Units
H (amp/m)
B (webers/m2)
  not less than not less than  
10 15,100 1,000 1.53
50 16,700 5,000 1.70
200 19,000 15,000 1.89


We typically aim to stock:

  • A range of bright-turned round bar section sizes between 5/8" (16mm) and 2" (51mm).
  • A range of black-rolled (as-forged) bar sizes from 2" (51mm) to 8" (203mm) diameter.
  • A selection of commonly-used flat/rectangular bar dimensions.
  • A selection of commonly-used plate dimensions, e.g. ½" (12mm) & 1" (25mm) thicknesses.
  • Anodes or rings can be cut to custom thicknesses from round or rectangular bar. These can be drilled with holes for fixings if required or further machining to specific requirements.
  • Many other profiles can be forged and pieces cut and/or machined to customer-specified dimensions on request, using our wide range of experienced sub-contractors.

Other sizes and specifications are available on request. Please contact us at