Evaluations of pure beryllium, plus 72 binary beryllium alloys. Bibliography through 1986. Required reference sources for engineers and scientists alike, each volume in the Phase Diagram Monograph Series presents the most complete, authoritative, and reliable phase equilibria information ever published on the alloys. Each volume comprises critical evaluations of individual alloy systems performed by experts under the ASM/NIST Data Program for Alloy Phase Diagrams. Evaluation involves searching the literature for all existing thermodynamic and related information on the system, assessing value and distilling the best data into a comprehensive report. Phase diagrams are plotted in atomic percent, but include a secondary weight percent scale. Important points are labeled with composition and temperature. Supplementary graphs provide enlargements of complex areas, solubilities and transformations on the phase diagrams, as well as ancillary drawings that show lattice parameters and thermodynamic data. The text includes discussion of stable and metastable phases, order-disorder and magnetic transitions, thermodynamic calculations and modeling, discrepancies in data values and controversial areas and uncertainties in the diagram. In addition, tables list invariant reactions, crystal structures, lattice parameters, experimental values and thermodynamic parameters.