FRICTION AND WEAR CHARACTERISTICS OF NATURAL IRON SAND COATING

摘要

Friction and wear characteristics of natural iron sand coating were experimentally examined in the absence of lubricant. The friction motion was not be continuous, but be intermittent and proceeded by a process of stick-slip. An oxide film, Fe_2O_3, was formed along the sliding marks, but the amount of coating worn away was slight. There is a striking similarity in the friction coefficient between the zinc/iron sand coating and MoS_2 over a load range of 20N to 1000N. The iron sand coating has a spongy structure and the bonding strength between the iron sand particles is so small that the metallic junction formed between sliding surfaces may be weaker than the substrate. Consequently the amount of metal removed may be small. In addition, the oxide film formed on coating is so soft and fluid that it may in itself function as lubricants and may play little part in abrading the other surface.