Reduction of the hot cracking sensitivity of CM-247LC superalloy processed by laser cladding using induction preheating

Guillaume Bidron (1, 2) , Anis Doghri (3, 4) , Thierry Malot (1) , Florent Fournier-Dit-Chabert (4) , Marc Thomas (4) , Patrice Peyre (1)

1 PIMM - Laboratoire Procédés et Ingénierie en Mécanique et Matériaux
2 APS Coatings
3 LEM3 - Laboratoire d'Etude des Microstructures et de Mécanique des Matériaux
4 DMAS, ONERA, Université Paris Saclay (COmUE) [Châtillon]

In the present work, the repair of CM-247LC superalloy has been investigated by using a laser cladding process. Since this material is well known for its high hot-cracking susceptibility in Heat Affected Zone during welding, repairing is quite challenging. In a first stage, a detailed investigation of the effect of cladding parameters on the crack susceptibility was carried out on coupons that received a low pre-heating condition. However, despite a reduction of crack sensitivity for low energy inputs, this material has systematically shown some evidence of cracking in the HAZ. In a second stage, attempts were made to reduce crack defects by using an induction preheating, with higher temperatures in the range of 800-1100°C. With the highest pre-heating temperatures near 1100°C, the partial dissolution of large γ' precipitates, combined with re-precipitation of secondary and smaller γ' precipitates were helpful to prevent hot cracking.

Mots clés: cladding; laser; CM-247LC; preheating

Domaines: Matériaux

Guillaume Bidron, Anis Doghri, Thierry Malot, Florent Fournier-Dit-Chabert, Marc Thomas, et al.. Reduction of the hot cracking sensitivity of CM-247LC superalloy processed by laser cladding using induction preheating. Journal of Materials Processing Technology, 2020, 277, pp.116461. ⟨10.1016/j.jmatprotec.2019.116461⟩. ⟨hal-02387460⟩