Abstract: A composite material is obtained by mixing with water 100 parts in weight of binder, between 250 and 800 parts in weight of steel-based shot having a granulometric distribution comprised between 120 jim and 3000 jim, between 10 and 15 parts in weight of non-densified silica fume and a highly water-reducing superplasticizer. The ratio between the weight quantity of water and the weight quantity of hydraulic binder is comprised between 0.16 and 0.25. The composite material presents a very high abrasion resistance, an abrasion index measured according to the C.N.R protocol comprised between 0.15 and 1.0, the value of the D10 grain size of the shot being at least eight times greater than the value of the D90 grain size of the hydraulic binder.

Abstract: A method for fine grinding of mineral particles consists of producing by atomization pellets, made from steel with a high carbon content, or cast iron, with a granular size range less than 15 mm and mixing the pellets with balls, made from steel or cast iron with dimensions between 20 mm and 120 mm, in a rotating grinding mill, the proportion by weight of pellets depending on the granular size of the mineral particles for grinding and the desired reduction ratio.