| 摘要 |
<p>In the cladding of an iron-carbon alloy workpiece, esp. of cast iron, with a foil, esp. of Cr-Ni steel, by means of an energy beam which melts both the foil and the workpiece surface to produce a solid bond, the depth of workpiece surface melting is the same as the foil thickness, the zones of material melted by the energy beam overlap each other without a gap and the clad workpiece, opt. after machining its rough surface, is stress relieved. The method is useful for cladding i.e. engine valve seats. The cladding has satisfactory toughness so that it is resistant to cracking and has high hardness and wear resistance which are retained during long term heating at 970 K. The steel foil pref. contains 17-20% Cr, 5-11% Ni and opt. 5-8% Mn and the cladding is pref. stress-relieved at 970K for about 1 hr. For cladding a valve seat, a frustoconical layer is melted by an energy beam moved in the seat periphery direction, pref. in a spiral path and the cladding is stress-relieved during running of the engine contg. the valve.</p> |
