Magnet steels

The Zond VD - 96 is intended for the detection of cracks, precipitates, inclusions etc. and corrosive defects with the preliminary estimation of their depth in various objects of magnetic and non - magnetic steels, non-ferrous and refractory metals and welds including coatings. 

Gobalt is also used in other magnetic steels and stainless steels, and in alloys used in jet turbines... 

It forms silver-white, rhombic crystals,7 of density 7-83, and melting point 1020° C. according to Hilpert and Dieckmann8 or 1031° C. according to Friedrich.9 It is non-magnetic. Steel-grey crystals of the arsenide of density 7-94 have been found associated with tin sulphide in the hearth of an old tin smelting furnace in Cornwall.10... 

However, up to 30% of the power consumption of a motor can be attributed to no-load losses because of windage (by cooling fan and air drag), friction in the bearings, and core losses that comprise hysteresis and eddy current losses in the motor magnetic circuit. Load losses include stator and rotor losses (resistance of materials used in the stator, rotor bars, magnetic steel circuit) and stray load losses such as current losses in the windings.f ... 

Amongst the non-ferrous alloys of chromium, nichrome, cochrome, stellite and magnet steels (p. 245) may be mentioned. 

The alloy known as stellite retains its hardness at high temperatures. It comprises Co 55, Cr 33 to 35, W 10 and C 1 5 to 2 and stellite bits are often used in rock boring instead of diamonds. It is used cast as it is too difficult to work. Magnet steels contain iron alloyed with the above four elements. A typical steel suitable for... 

Cobalt is a component of the so-called superalloys used to make critical parts of jet engines, gas-turbines, and of other machines operating under stress at high temperatures. It is also a component of the so-called stellites. These alloys are composed of 50-60% cobalt, 30-40% chromium and 8-20% tungsten, and are valued for their extreme hardness, strength, and heat resistance. In addition, cobalt is a component of magnetic steels and aluminum alloys with superior ferromagnetic properties. In 1975,... 

Fig. 3 Experimental setup for etmtFollmg feiroilmd droplets. The eoils are etehed on a double-sided printed eircuit board. The gray eoils are (m the back of thePCB. The PCB is placed on a soft magnetic steel sheet with two permanent magnets at either side. The magnetic field of the two permanent magnets polarizes the magnetic particles in the ferrofluid droplet...

Table i. .3-2 Standard lEC specification for non-alloyed magnetic steel sheet. The conventional designation of the different grades (first column) comprises the following order (1) 100 times the maximum specified loss (Wkg ) at 1.5T (2) 100 times the nominal sheet thickness in (mm) (3) the characteristic letter D (4) one tenth of the frequency in Hz at which the magnetic properties are specified. The materials are delivered in the semi-processed state. The magnetic properties apply to test specimens heat-treated according to manufacturer s specifications... 

In the case of low Si steels (< 1 wt% Si), the last two annealing steps are applied by the user after lamination punching (semi-finished sheet). Table 4.3-15 lists the specifications, including all relevant properties for non-oriented magnetic steel sheet. 

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