NEAR NET SHAPE PROCESSING OF METAL AND CERAMIC COMPOSITE INGOT MOLD

A new pressureless infiltration method was developed to place a silico n dioxide particle reinforced layer on the surface of an industrial in got mould without changing the production process of the ingot mould. The morphology and structure of the composite layer were investigated by optical and scanning electron microscopy. The service life and ther mal characteristics of the reinforced mould were tested during their u se in practical casting processes. It was found that a 4 mm thickness composite layer can be obtained on the surface of an ingot mould with this method. The reinforced mould can be used directly without any ext ra machining process. The service life of the new mould is twice that of the original for the same application conditions. The heat resistan ce and wear resistance of the mould were evidently improved. (C) 1997 The Institute of Materials.