Sobre a influência da carga normal e do tamanho da partícula no desgaste abrasivo de materiais elastoméricos empregados na indústria de beneficiamento de minério

Abstract

Elastomeric materials, such as polyurethanes and rubbers, are widely used in the mining industry because of their moderate cost and excellent mechanical properties. Such polymers have been used mainly in transportation and screening for their appreciable abrasion wear resistance.Previous work on abrasive wear of elastomers reported the influence of grit size, sliding distance and normal load on wearrate. However, the way how those parameters affect the wear rate is not clear yet.In this study, the abrasive wear behavior of a group of polyurethanes and rubbers were investigated at room temperature according to a rotary drum abrasion method (ASTM D 5963). Pin-on-drum arrangement wear tests were carried out at 26 cm/s test speed and load value of 5 N and 10 N. Corundum paper grid varying from 60 to 400 mesh were used as an abrasive drum surface and their surface topography acquired from 3D profilometer. After each 40 meters, the mass loss of the pin was recorded until reaching 120 meters. The wear coefficient was deduced from wear volume.The materials have been characterized by Shore A hardness and FTIR methods. The wear micromechanisms were investigated by the SEM and related to the corundum paper topographical parameters.Most of polyurethanes show better wear resistance than rubbers. Wear mechanisms vary with abrader grit from Schallamach waves to microcutting and microploughing. Low correlation between ShoreA hardness and wear was observed