Ferromaster为德国List-Magnetik公司的磁导率仪，英文资料如下

Magnet permeability meter Ferromaster

Measuring device to determine the relative magnetic permeability µr

Paramagnetic materials up to permeability µr=2

With the Magnet permeability meter List-Magnetik Ferromaster you can easily determine the relative magnetic permeability µr of feebly magnetic materials and workpieces with a permeability between 1.001 and 1.999.

The permeability is measured by touching the workpiece with the probe tip and reading the result from the display.

The magnetic permeability or magnetic conductivity makes a statement as to how strong a material is magnetizable.

Testing of stainless steel and other low magnetic materials

Typical applications are: non-destructive testing of materials, e. g. quality control of stainless steel, material selection for electron-/ion-beam equipment, detection of material defects induced by mechanical or thermal stress. Standard-compliant permeability measurements according to ASTM A342 Test Method 4, EN 60404-15 Procedure 6 and VG 95578 can be carried out with the Ferromaster.

ASTM A342 Test Method 4, EN 60404-15 Method 6 and VG 95578

The probe head contains a permanent magnet that magnetizes the sample near the probe tip. Two sensitive magnetic field sensors in differential circuit measure the field distortions caused by the magnetization of the sample. The device is calibrated to precisely calibrated reference standards from the National Physical Laboratory (NPL, Teddington, UK). Recalibration is easy. A calibration standard is included with every device.

As a special feature, the Ferromaster is equipped with a robust, waterproof hand-held housing (protection class IP65) and is therefore ideal for use in harsh industrial environments. The built-in battery enables approx. 50 hours of operation.

The magnetic permeability of a material generally depends heavily on the strength and frequency of the magnetizing field. The probe head of the Ferromaster contains a permanent magnet that generates a constant magnetic field of around 35 kA/m at the test probe.

Ferromaster works with a saturation core and 2 alternating field coils according to the fluxgate principle and can measure permeabilities in the measuring range between 1.000 and 2.000. Above this measuring range, the saturation cores are too saturated and no longer result in a linear measurement.

The measured value of the permeability depends on the dimensions of small samples. The sensitivity of the device takes z. B. with the thickness of the sample.
From a sample thickness of around 5 mm and a lateral extent of around 2 cm, the measurement is independent of the size.