SciELO - Scientific Electronic Library Online

 
vol.19 número2Efeito dos modos de transferência e da composição de gás de protecção na emissão de partículas ultrafinas na soldadura MAG de açosManufatura Aditiva: o papel da soldagem nesta janela de oportunidade índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Soldagem & Inspeção

versão impressa ISSN 0104-9224

Resumo

VAZ, Cláudio Turani  e  BRACARENSE, Alexandre Queiroz. The influence of PTFE used as basic covered electrode binder on weld metal acicular ferrite formation. Soldag. insp. [online]. 2014, vol.19, n.2, pp.177-189. ISSN 0104-9224.  http://dx.doi.org/10.1590/0104-9224/SI1902.10.

Weld metals obtained from covered electrodes agglomerated with polytetrafluorethylene (PTFE) presented ultra low diffusible hydrogen content and appreciate quantities of acicular ferrite. This paper investigated the polymer influence on its constituent formation. The microstructure produced by consumables containing this component presented acicular ferrite quantities higher than expected on the literature for weld metals with same carbon, silicon and manganese content. This difference could not be related to welding parameters employed. The residual chemical elements evaluation indicated nitrogen as the main responsible by the microstructural variances observed. The operational characteristics of classic E7018 and polymer agglomerated electrodes showed the less weld metal nitrogen absorption must be associated to two main factors. The dissolved nitrogen of the metallic drops collected during the polymer agglomerated electrode welding showed most effective shielding atmosphere. The carbon content of polymer agglomerated electrode indicated an atmosphere rich on its element. This is in accordance with a best shielding process hypothesis. The metallic drops average size, dissolved nitrogen content as a function of size and voltage oscillograms indicated metallic transfer mode changes.

Palavras-chave : basic covered electrodes; polymers; metallic transfer; nitrogen; acicular ferrite.

        · resumo em Português     · texto em Português     · Português ( pdf )

 

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons