| 摘要 |
PURPOSE:To obtain a roll for heat treatment furnace having excellent adhesivity, wear resistance and build-up resistance by forming the thermal-sprayed intermediate layer and the thermal-sprayed film most upper layer adding stabilized zirconia to mullite raw powder with the thermal-spray in order on metal layer for combination formed on the roll surface. CONSTITUTION:On the metal layer (NiCr) for combination formed with the thermal-spray on the surface of the roll base material, the thermal-sprayed intermediate layer composed of mixed material of the mullite, metal for combination and zirconia (20-70vol.% to the mullite) containing 5-20wt.% one or more kinds of MgO, CaO and Y2O3, is formed. Successively, on this thermal-sprayed intermediate layer, the thermal-sprayed film uppermost layer composed of the mixed material of the mullite and the zirconia (20-70vol.% to the mullite) containing 5-20wt.% one or more kinds of MgO, CaO and Y2O3 is formed. By this method, the hearth roll having excellent high temp. adhesivity, wear resistance and build-up resistance and largely extending the service life, is obtd. |
