| 학회 | 한국재료학회 |
| 학술대회 | 2007년 가을 (11/02 ~ 11/02, 성균관대학교) |
| 권호 | 13권 2호 |
| 발표분야 | 구조재료 |
| 제목 | Three-dimensional analysis of thermal stress and prediction of failure of Ni-Al2O3 Functionally Graded Material (FGM) |
| 초록 | Functionally Graded Materials is a technique where dissimilar materials can be joined by varying its composition continuously to minimize its residual stress. Recently, FGM is widely used as a boundary layer for multi-layer structure, binder, energy transformation materials, electronic materials, bio-materials, structure materials and etc. Therefore, FGM has been used in joining of various materials such as metal, ceramics, resin and etc. In this work, we fabricated a crack-free joining of Ni and Al2O3 using functionally graded method. Appropriate proportions of Ni and Al2O3 were dispersed and mixed in ethanol solvent so that various compositions of graded layer were made. Each composition was stacked to make a green body. This green body was cold pressed, followed by CIP (Cold Isostatic Press) and sintered in pressureless sintering furnace at 1350℃ in Argon atmosphere. Finally, it was cooled at 2℃/min to minimize its residual stress during processing. Moreover, the particle size of Nickel and Al2O3 powders were varied to improve the density of green body so that the shrinkage can be minimized during sintering. Moreover, ANSYS simulation tool was used to calculate and to optimize the thickness and the number of layers for its crack-free joining. As a result, crack-free joining of Ni-Al2O3 sample was obtained, and hardness and modulus of each graded layer were measured using an indenter. These experimental values matched the calculated results, obtained by simulations and this analysis is proven to be useful where residual stresses are very difficult to measure experimentally. |
| 저자 | 박종하1, 류새희1, 이선영1, 이재철2, 안성훈2, 좌용호1 |
| 소속 | 1한양대, 2서울대 |
| 키워드 | FGM(functionally graded material); Ni-Al2O3 joining; crack free; ANSYS simulation |
