| 摘要 |
An article (3) of relatively low friction material is provided with a relatively high friction insert portion (12,13) by forming an aperture (10,11) where the portion is to be located, making the portion in the form of an insert of a different cross-sectional shape which constitutes an interference fit in the aperture, followed by forcing the insert into the latter until only a relatively small portion of the insert projects from the surface of the article. |
