Journal of Crystal Growth, Vol.218, No.2-4, 381-389, 2000
Compositional variation and precipitate structures of copper-beryllium single crystals grown by the Bridgman technique
The Bridgman technique was used to produce Cu-1.8 wt% Be single crystals. The growth methodology is presented and optimal growth conditions for the production of CuBe single crystals utilizing the Bridgman technique were determined. The influence of material purity, the temperature profile, and the translation rate on the crystal growth process are discussed. The as-grown single-crystal material produced was investigated with optical microscopy, scanning electron microscopy, X-ray diffraction, and spectrometry techniques. Segregation of impurities and alloying elements occurred as a consequence of recrystallization and resulted in a variation of composition over the length of the single crystals grown. The compositional variation was characterized for crystals that underwent single and double solidification passes. Structures occurring at multiple length scales were documented throughout the single crystal material. Precipitate structures consisting of beta- and gamma-phases in a Cu-rich cc-matrix were identified. Structures aligned with the {100} planes of the parent phase were also observed.
Keywords:copper-beryllium;crystal growth;Bridgman growth;compositional variation;precipitate structures