Low-Alloy White Irons

Unalloyed White Iron Low-Alloy White Iron Martensitic White Iron (Ni-hard) High-Carbon, High-Chromium, White Iron... 

The British Standard BS 4844 1986 defines three grades of low-aUoy white irons shown in Tables 10-1 and 10-2. These alloys have been superseded by alloyed irons. 

Low-alloy white cast iron. Low-alloy white cast iron has improved toughness and wear resistance. The main limitation is that a better performance or a longer life must justify its extra cost. 

The white cast irons and their low alloys have good abrasion resistance properties [2,3]. White cast irons are used for grinding balls, segments for mill liners and slurry pumps. In the ceramic industry they are used for muller tyres and augers in the pulp and paper industry for attrition mill plates and chip feeders and in the paint industry for balls for grinding pigments. 

The corrosion resistance of unalloyed and low-alloy flake, nodular, malleable and white cast iron is comparable to mild- and low-alloy steel. However, these cast irons have a major advantage over steel namely, greater cross section or wall thickness than steel. Consequently, they have a... 

Ferritic nitrocarburizing is a subcritical heat treatment process, carried out by either gaseous or plasma techniques, and involves the diffusion of carbon and nitrogen into the ferritic phase. The process results in the formation of a thin white layer or compound layer, with an underlying diffusion zone of dissolved nitrogen in iron, or alloy nitrides (Ref 17). The white layer improves surface resistance to wear, and the diffusion zone increases the fatigue endurance limit, especially in carbon and low-alloy steels. Alloy steels, cast irons, and some stainless steels can be treated. The process is used to produce a thin, hard skin, usually less than 25 xm (1 mil) thick, on low-carbon steels in the form of sheet metal parts, powder metallurgy parts, small shaft sprockets, and so forth. 

Steels white iron, low alloy steels and stainless steels [51-54]... 

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