Abstract

NASCIMENTO, Marcelino P; VOORWALD, Herman J. C.  and  GAMARRA-ROSADO, Víctor O.. Efectos Del Proceso De Soldadura Tig En La Resistencia A Ensayos Por Fatiga Del Acero Aeronáutico Abnt 4130. Rev. LatinAm. Met. Mat. [online]. 2003, vol.23, n.2, pp.36-44. ISSN 0255-6952.

This study has as objective to analyses the effects of the TIG welding process on structural integrity of ABNT 4130 steel, widely used in welded aeronautical structures, by fatigue crack growth tests located in three different areas: base material, heat affected zone (HAZ) and weld pool. The specimens were made in accordance to ASTM 647 standard, from hot rolled plate containing 0,80 mm of thickness, which was determinate from previous studies of welded tubular structure failures of T-27 Brazilian aircrafts. The tests were carried out on centre-cracked tension (CCT) specimens conduced in room temperature, constant amplitude range, at a frequency of 10 Hz, and load ratio R=0,1. The results obtained were associated to the microstructure and microhardness variations of the mentioned areas. It was observed that the fatigue crack located in the weld pool grew more quickly, followed for that located in HAZ and, finally, for that contained in the base material.

Keywords : Crack growth; Fatigue crack; Welded aeronautical structures; TIG welding process; ABNT 4130 aeronautical steel..