Estudo de Formulações e das Variáveis de Fabricação de um Suporte de Solda Cerâmico (Study of Formulations and the Manufacturing Variables of a Ceramic Weld Backing)

This work presents a methodology for the in lab manufacturing of a ceramic backing for the one-side steel welds. Formulations were prepared using cordierite, bauxite and magnesite as refractory minerals. Bentonite and sodium silicate were used as addictives for the ceramic blend. The manufacturing process included dry mixture, compressing, drying and sintering of the specimens. The weld supports were characterized by X-ray diffraction, optical microscopy of the surface, water absorption and flexile tension. Also they were submitted to the welding of the root pass with the MIG-MAG process. The results show that the conventional ceramic manufacturing route is adequate for the production of the ceramic weld backing. Among the tested formulations, cordierite showed better integrity both during its manufacturing and during the welding operation, producing well shaped weld beads, free from discontinuities. The manufacturing variables were evaluated, such as the compacting pressure, sintering temperature and the amount of water added to the ceramic mass.