An Approach to Calculate Linear Abrasive Wear Rate of Soil-engaging Implements’ Surfaces

Abstract. Soil-engaging implements play an important role in agricultural machinery. Their surfaces always come to failure because of soil‘s friction, which is mainly due to abrasion. Since abrasives can both slide and roll across the surfaces, soil abrasion to implements should be categorized into the three-body type. Between soil abrasive particles there are some liquid and organic substances, thus forming an inter-adhesion effect and making soil unlike metals or minerals. This paper tries to propose a method so as to theoretically calculate the linear rate of wear caused by soil rubbing. Firstly the wear behaviors are divided into two different kinds, i.e. sliding wear and rolling wear. To modeling sliding wear a previous research achievement by Zum Gahr is referred, but some new conditions and derivations are completed. Secondly inspired by the fatigue part in sliding wear model, rolling wear is also attributed to be fatigue cause by repeated plastic deformation. Then given wear rate by a single particle, the wear rate of per unit area on implements‘ surfaces can be calculated a step further. Since particles in actual soil are not uniform, this paper presents a way to describe abrasive particle‘s geometrical features referred from Stachowiak‘s work. At last a force model is built to simulate the situation of particles piercing into implement‘s surface during abrasion, and the boundary conditions between sliding and rolling are derived. With all these parameters known the linear abrasive wear rate of an actual soil-engaging implement‘s surfaces can be calculated as a result.