Influence of the mechanical properties of filler materials on weld repair quality of SPF tools
Résumé
In superplastic forming (SPF) of titanium alloy sheets, the thermomechanical stresses due to successive forming cycles are likely to provoke early degradation and even fracture of dies. For economic reasons, dies are generally weld-repaired in order to extend their service life. A weld repair technique was developed for high nickel high chromium heat resistant alloys using shielded metal arc welding process. This paper focuses on the influence of the preheating and the buttering with a low strength filler metal on the quality of the welded zones in order to optimise the procedure of SPF tool repair. A double approach including numerical simulation using SysweldTM and experimental investigations is proposed.