ALLOY-COATED BOILER PART AND METHOD OF WELDING SELF-FLUXING ALLOY-COATED BOILER PART

摘要

[PROBLEMS] To provide an alloy-coated boiler part that at all regions to be protected, is furnished with a weld deposit coating of alloy material excelling in erosion/corrosion resistance and that even when joined by welding, is free from thermal shock cracking. [MEANS FOR SOLVING PROBLEMS] Superalloy coating (15) is applied over rapid temperature rise region (C), where thermal shock cracking may occur at welding operation, at edges subjected to weld joining together with the vicinity thereof. On the other hand, self-fluxing alloy coating (16) is applied on any remaining regions other than the rapid temperature rise region (C). While over a half proportion of each of the alloy coatings (15,16) is occupied by an Ni-enriched Ni-Cr component, the superalloy coating (15) has the contents of B and Si suppressed to <=0.1% and <=0.5%, respectively, and in the self-fluxing alloy coating (16), the content of each of B and Si is in the range of 1 to 5%.