| Title |
Development of Insert Metals for the Transient Liquid Phase Bonding in the Directional Solidified Ni Base Super Alloy GTD 111 |
| Authors |
이봉근(Bong Keun Lee); 오인석(In Seok Oh); 김길무(Gil Moo Kim); 강정윤(Chung Yun Kang) |
| ISSN |
1738-8228(ISSN), 2288-8241(eISSN) |
| Keywords |
transient Liquid phase bonding; directionally solidified Ni base superalloy; GTD111; filler metal; wide-gap brazing; powder; microstructure |
| Abstract |
On the Transient Liquid Phase Bonding (TLPB) phenomenon with the MBF-50 insert metal at narrow gap (under 100), it takes long time for the bonding and the homogenizing. Typically, isothermal solidification is controlled by the diffusion of depressed element of B and Si. However, the amount of B and Si in the MBF-50 filler metal is large. This is reason of the long bonding time. Also, the MBF-50 filler metal did not contained Al and Ti which are γ` phases former. This is reason of the long homogenizing time. From the bonding phenomenon with the MBF-50 insert metal, we search main factors on the bonding mechanism and select several insert-metals for using the wide-gap TLPB. New insert-metals contained Al and Ti which are γ` phases former and decrease the B then the MBF-50. When the new insert-metal was used on the TLPB, the bonding time was decreased about 1/10 times and homogenizing heat treatment was no needed. In spite of the without homogenizing, the volume fraction of γ` phases in the boned interlayer was equal to homogenizing heat treated specimen which was TLPB with the MBF-50. Finally, the new insert metal named WG1 for the wide-gap TLPB is more efficient then the MBF-50 filler metal without decreasing the bonding characteristic. |