Laser repairing surface crack of
Ni-based superalloy components
Ni-based superalloy components
(1. State Key Laboratory of Laser Technology,
Huazhong University of Science and Technology, Wuhan 430074, P.R.China;
2. Department of Powder Engineering, Huazhong University of
Science and Technology,Wuhan 430074, P.R.China)
Huazhong University of Science and Technology, Wuhan 430074, P.R.China;
2. Department of Powder Engineering, Huazhong University of
Science and Technology,Wuhan 430074, P.R.China)
Abstract: Surface crack of components of the cast nickel-base superalloy was repaired with twin laser beams under proper technological conditions. One laser beam was used to melt the substrate material of crack, and the other to fill in powder material to the crack region. The experimental results show that the surface crack with the width of 0.1~0.3 mm could be repaired under the laser power of 3 kW and the scanning speed of 6~8 mm/s. The repaired deepness of crack region is below 6.5 mm. The microstructure of repaired region is the cellular crystal, columnar crystal dendrite crystal from the transition region to the top filled layer. The phases in repaired region mainly consisted of supersaturated α Co with plenty of Ni, some Cr and Al, Cr23C6 , Co2B, Co-Ni-Mo, Ni4B3 , TiSi and VSi. The hardness of filled layer in repaired region ranged from HV0.2450 to HV0.2500, and the hardness decreases gradually from the filled layer to joined zone.
Key words: van of aviation engine; surface crack; laser repairing, nickel-base alloy
CLC number:TN249; TG159.99
CLC number:TN249; TG159.99