摘要 |
In a cast composite wear part consisting of a metallic matrix having wear resistant inserts in the or each working face, the inserts are formed from a ceramic wafer which consists of a homogeneous solid solution of 20-80 wt.% Al2O3 and 80-20 wt.% ZrO2 and which is impregnated with liquid metal during casting. Preferably, the ceramic material consists of 55-60 wt.% Al2O3 and 38-42 wt.% ZrO2 or 70-77 wt.% Al2O3 and 23-27 wt.% ZrO2 and is present in amount 35-80 (preferably 40-60, especially about 50) wt.% in the insert. Also claimed are (i) a cast composite wear part consisting of a metallic matrix containing two or more adjacent ceramic wafers with minimal spacing (preferably about 10 mm to allow liquid metal entry); and (ii) a cast composite wear part consisting of a metallic matrix including a wear resistant ceramic wafer in the form of a honeycomb structure, the cells having a polygonal or circular shape and the cell wall thickness preferably being 5-25 mm. |