抄録
The relation between the changes in surface appearance and wear of a specimen was observed. The specimen was pin-shaped having a cone tip of 90°C. It was slid on a hardened bearing steel disk at a sliding speed of 16.7cm/sec. under a load of 0.5-2kg in a dry condition. Appearances of the surface were examined by measuring contact resistance and by optical method.
The results obtained were as follows:
1) Specimen of 6:4 brass containing lead: The metal adhered to the disk was little in amount and the wear of the specimen was relatively small in the earlier stage. However, severe wear was initiated when the disk was covered with the transferred metal.
2) Specimen of pure iron: The wear of the specimen linearly increased with sliding distance, and no remarkable changes were observed on the sliding surface during the friction up to 1, 000m.
3) Specimen of 7:3 brass: The wear process corresponded well with appearances of the sliding surface. For instance, the wear decreased when an oxide was formed on the surface, but it again increased after the break-down of the oxide film.
4) Specimen of 4% Sn-Cu alloy: Low contact resistance and low coefficient of friction were observed in the earlier stage, and severe wear abruptly occurred after sliding for some distance. However, the wear was retarded when high contact resistance and high friction, which indicated the formation of the oxide, were observed. No break-down of oxide film was observed for this alloy.
