6Bever M B, Duwez P F. Gradient in Composite Materials. Materials Science and Engineering, 1972(10) : 1 - 8.
7Okamura H. State of the art of material design projects for severe service applications. Materials Science and Engineering A, 1991, 143(1/2) : 3 -9.
8Kimura H, Toda K. Design and development of graded materials by pulse discharge resistance consolidation. Metal Powder Report, 1997, 51:34-34.
9Teng L, Wang F, Li W. Design and synthesis of Ti-ZrO2 functionally graded materials. Journal of University of Science and Technology Beijing: Mineral Metallurgy Materials, 2001, 8 ( 1 ) :48 -52.
10Elkedim O, Gao H S, Guay D. Preparation and corrosion behavior of nanocrystalline iron gradient materials produced by powder prcessing. Journal of Materials Processing Technology, 2003, 121 (2/3) : 383 -389.
