INVESTIGATION OF MECHANICAL AND MICROESTRUCTURAL CHARACTERISTICS PROVIDED BY HIGUCHI AND MODIFIED HIGUCHI METHOD IN BUTTERING WELDING OF AN ASTM A182 F22 STEEL WITH AN ER 80S-G WIRE.

Válter Figueiredo Montello Júnior¹; Thiago Henrique Fernandes Dias Ferrão¹; Humberto Vinícius Muñoz Aguirre¹; Fabrício Pereira Medeiros¹; Carlos Alberto Mendes da Mota¹; Alexandre Saldanha do Nascimento¹

¹ Universidade Federal do Pará

doi:10.20906/CPS/COB-2015-2230

Resumo

This work intends to develop experimental validation, investigating, mechanically through micro hardness testing and microstructurally by optical microscopy, the predictions determined by Higuchi and modified Higuchi method, respectively, the buttering welds in three layers of an ASTM A182 F22 steel plate deposited by GMAW using an ER 80S-G steel wire. The influences of thermal cycles imposed by depositions of each buttering layer in the base metal HAZ were observed. It was verified that the deposition of the second layer was able to refine the HAZ-CG and temper the hard zones of base metal HAZ. It was also observed that the last layer does not interfered in the action planned by the previous heat cycle, which would result in new regions of hard areas and coarse grains, weld embrittlement areas. Thus, the use of Higuchi method as a tool for welding of these materials is satisfactorily acceptable.

Palavras-chave: Buttering; Higuchi; HAZ; Microhardness; Microstructure