309 MMC/Al 合金複合材料の動的破壊靭性の改善

抄録

From the above result, a two-layers structure has improved the greatest problem of the low-toughness of MMC, from the field of structure.. The results obtained are summarized as follows : (1) The fatigue strength of a two-layers structure was the same as AC4CH material at the fatigue strength of Nf=1×(10)^7. (2) As a result of macroscopic observation, the destructive form of a twolayers structure had two different. (3) The origin part of a two-layers structure was the MMC section, and the final fracture was near the angle of aluminum alloys. (4) As a result of observing fracture of a two-layers structure in detail, fatigue fracture surface of face centered cubic lattice was seen from the border plane at the aluminum side. From this result, the fracture mechanism of a two-layers structure was what the fatigue crack initiation from MMC stops in a border plane, what a crack generates by face centered cubic lattice characteristic shearing strain of aluminum, carrying out ductile fracture and the last fractured. (5) From the above result, a two-layers structure type MMC has improved the consequence factor of the low-toughness of MMC. In addition, it is effective in making fatigue crack propagation stop, and has solved that it was material with high added values.