Bonding sintered hard alloy to cast alloy - by casting alloy onto sintered alloy coated with ferrous paste contg. low m.pt. components

摘要

Permanent connection between a sintered alloy contg. more than 50 wt.% hard material (esp. an iron-gp. metal-cemented TiC alloy) and a cast alloy is produced by applying a paste of a ferrous alloy contg. one or more of BiSi and P (esp. an iron alloy contg. a few percent of B and/or Si and/or P and less than 1% C) to the sintered alloy, drying the coating or fusing it into the alloy, placing the alloy in a casting mould and casting the other alloy onto the sintered alloy. An excellent bond is produced between the alloys and the surface of the sintered alloy does not have to be prepared (e.g. by machining) before bonding. The method allows hard regions to be formed on castings in selected areas where wear resistance is required.