| 摘要 |
A chain saw guide bar includes outer side surfaces, a longitudinal groove having side walls, and two edge surfaces. Each edge surface interconnects a side wall and an outer side surface to form therewith inner and outer corners, respectively. To edge-harden the guide bar, the edge surfaces, inner corners, and outer corners are heated above 750 DEG C. Then, the edge surfaces and inner corners are rapidly cooled, i.e, quenched, but the outer side surfaces are cooled more slowly, whereby the inner corners are given a higher hardness than the outer corners. |
