Abstract: An improved grinding ball may include a carbon content of 1.1 to 1.4 wt %, a chromium content of 10 to 14 wt %, a manganese content of 0.8 to 1.5 wt %, a silicon content of 0.6 to 1 wt %, a molybdenum content of less than 1 wt %, a nickel content of less than 1 wt %, any impurities with a total content of less than 0.5 wt %, the balance to obtain 100% being iron. The grinding ball includes a discrete distribution of chromium carbides as opposed to a network distribution.

Abstract: The mill comprises a cylindrical shell ring (10) revolving about its longitudinal axis and containing a grinding charge comprising grinding bodies made of metal alloy. At least one grinding body (30) identical to those that make up the grinding charge is fixed to an elastomer or rubber pedestal (28), itself fixed to the interior surface of the shell ring. This grinding body (30) is exposed to the conditions inside the mill and is associated with a reference electrode (36) from which it is electrically insulated. This reference electrode (36) is protected from the impact knocks of the charge in the mill but is in electrical contact with the pulp in the mill, the said grinding body (30) and the said electrode (36) being electrically connected to measurement apparatus (18) fixed inside the shell ring of the mill.

Abstract: The mill comprises a cylindrical shell ring (10) revolving about its longitudinal axis and containing a grinding charge comprising grinding bodies made of metal alloy. At least one grinding body (30) identical to those that make up the grinding charge is fixed to an elastomer or rubber pedestal (28), itself fixed to the interior surface of the shell ring. This grinding body (30) is exposed to the conditions inside the mill and is associated with a reference electrode (36) from which it is electrically insulated. This reference electrode (36) is protected from the impact knocks of the charge in the mill but is in electrical contact with the pulp in the mill, the said grinding body (30) and the said electrode (36) being electrically connected to measurement apparatus (18) fixed inside the shell ring of the mill.

Abstract: The invention relates to a process for producing cast wearing parts of high-carbon alloy steels having the composition expressed in weight % of: carbon 0.6 to 2% manganese 0.5 to 6% chromium   1 to 6% silicon 0.4 to 1.5% the balance being iron with the usual impurity contents, showing as structure selected from the group consisting of: a non-equilibrium structure of fine pearlite, containing between 1 and 1.5% by weight of carbon with a hardness lying between 47 and 54 RC; a high carbon austenitic structure with a hardness lying between 15 and 30 RC; a high carbon martensitic structure with a hardness lying between 60 and 65 RC, comprising the steps of subjecting steel of the indicated composition, after casting and complete solidification, to a cooling from a temperature of at least 900° C. at a cooling rate lying between 7.5 and 1.0° C./sec down to 500° C. and a cooling rate lying between 2° C.

Abstract: Alloyed steel with high carbon content having a composition, expressed in percentage weight: carbon from 1.1 to 2.0%, manganese from 0.5 to 3.5%, chromium from 1.0 to 4.0%, silicon from 0.6 to 1.2%, the remainder being iron with the usual impurity content, such that it provides a metallographic structure mainly of non-equilibrium fine pearlite and that its hardness is between 47 Rc and 54 Rc.