摘要 |
<p>PORTED ENGINE CYLINDER LINER WITH SELECTIVELY HARDENED BORE Selective laser case hardening is applied to the blended port relief area of the bore of a cast iron, water jacketed, engine cylinder liner to provide improved resistance to scuffing resulting from the rubbing contact of the walls and piston rings of an associated piston. The upper liner bore above the port relief may also be laser hardened to improve wear resistance. Case hardening of the selected area is performed by utilizing a traversed laser beam, preferably forming a single path helical pattern on the liner surface. The port relief area is preferably fully hardened by utilizing a closed helical pattern, while the upper bore may, if desired, be only partially hardened by increasing the lead of the helix to provide an open helical pattern.</p> |