TEM INVESTIGATION OF IRON SEGREGATION MODES IN CUALFE DILUTE ALLOYS

Iron has a very low solubility in copper (a few % at 1000 degrees C) a s well as in the ct solid solution of the Cu-Al alloy. We describe her e the iron segregation modes which are observed during the slow coolin g of the alpha (FCC) and beta (BCC) solid solutions of CuAlFe alloys c ontaining about 10 wt% Al and 4% Fe. At high temperature iron at first precipitates into ct or Gamma Fe; then at lower temperature iron-rich phases are observed containing also Cu and Al. Particularly, the alph a(2) phase appears very quickly, and it is thought to be richer in Fe than the alpha matrix.