Correlation between hardness and abrasive wear of grinding balls

Abstract

The grinding ball is manufactured by the Algerian Foundries (ALFET – Tiaret). It is used by the cement industry to transform the rock into fine, used in the cement manufacture. This product undergoes very frequent wear. This wear occurs in various forms (abrasion wear and impact wear) and each has a varying impact on this product life. Abrasion wear is the result of friction between many surfaces (rock, crusher shielding and balls between them), between which a sliding contact occurs, and causes a metal wrenching and a mechanical disintegration of these surfaces. The impact wear is the result of the shock between these surfaces (rock, crusher shielding and balls) and the ball that hits these surfaces from multiple angles, causes their disintegration. Generally, wear resistance improves when hardness increases and a very hard material is more resistant to wear because it less risk to seize in presence of particles abrasive and it opposes their penetration in its surface layer. Wear is estimated, in this work, by the mass loss of the heat-treated balls. A correlation between the hardness and abrasive wear of the balls is established in this work.

Grinding Media in Ball Mills-A Review

“…In the ball mill, friction is formed due to the difference between surfaces of adjacent grinding balls in the abrasion zone, whilst impact is due to rock-ball impact and ball-ball impact in the impact zone, as shown in Figure 8. In a series of experiments done by Aissat et al [42], smaller diameter balls of 50mm had a higher wear rate than larger diameter balls of 70mm. This was due to the higher percentage of chromium in the 70mm balls as compared to the 50mm balls.…”

“…where: K is the maximum breakage rate factor x is size of particle to be ground D is the ball diameter It has been shown by experiments that increasing hardness of the grinding media also increases the abrasion resistance of the media, but it is not the only factor. Therefore, the correlation between corrosion resistance and hardness has to be established [42]. Although there have been many ball mill power models up to date, they do not incorporate the effect of media shape, which has been shown by many studies that it has a significant effect on load behaviour inside the mill [45].…”

Effect of Subcritical Treatment (Tempering) on Hardness and Wear of High Chromium White Cast Iron

“…It is manufactured by the Algerian Foundries (ALFET -Tiaret) in high chromium white cast iron with 12 to 17% Cr. It undergoes abrasion wear that result of friction between many surfaces (rock, crusher shielding, and balls between them), between which a sliding contact occurs, and causes a metal wrenching and mechanical disintegration of these surfaces [18].…”