The cam-tappet of an I. C. engine is a rubbing pair with high load and
severe lubrication condition. In order to raise the antiscuffing capa
city of the cam-tappet, a laser microprecision treatment was adopted t
o make the topography with artificial regular asperities on the workin
g surface of tappets. It was proved by experiment using a full-scale e
ngine rig that the tappets treated by laser microprecision had an obvi
ous antiscuffing effect.