@article{oai:u-ryukyu.repo.nii.ac.jp:02007415, author = {平敷, 兼貴 and 糸村, 昌祐 and Heshiki, Kenki and Itomura, Shosuke}, issue = {10}, journal = {琉球大学理工学部紀要. 工学篇, Bulletin of Science & Engineering Division, University of the Ryukyus. Engineering}, month = {Sep}, note = {This paper is a report of an attemption to controll the microstructure of the Al-Cu eutectic alloy by means of unidirectional solidification in the Nickel-Chrome wire wound vertical electric resistance furnace to study the relationship between the solidification condition and the microstructure and the tensile strength of the controlled eutectic specimen. The experimental valiables; solidification rate (R cm/hr) and thermal gradient in the liquid at the liquid-solid interface (G℃/cm) are changed from 10.9cm/hr to 0.6cm/hr and 52℃/cm, 77℃/cm, respectively. The main results are obtained as follows: 1) It is able to controll the microstructure to be appropriate parallel to the direction of solidification. 2) If the ratio of the thermal gradient in the liquid (G) to the solidification rate (R) during unidirectional solidification was over a certain critical value (at this experiment, that value was 77.6) a eutectic colony microstructure was not formed. 3) There is a special relationship between the solidificaton rate (R) and the interlamellar spacing (λ), ie λ∝R^<-n> : n has a value of 0.49. 4) At higher solidification rate, the strength of unidirectional solidified specimen is higher than that of raw material solidified in the metal mould, but at lower conditions, for example 0.6cm/hr in this work, the strength of the test specimen is less than that of raw material because of the faults of lamellar structure and the decreasing of strengthening effect of CuAl₂ phase., 紀要論文}, pages = {71--80}, title = {一方向凝固させたAl-Cu共晶合金の組織および強度}, year = {1975} }