The chemistry and metallurgy of beryllium

Abstract

Beryllium (Be), the first of the group 2 alkali-earth ele­ments, is a silver-gray metal possessing an unmatched combination of physical and mechanical properties, which are vital for a variety of applications that offer tre­mendous benefits to society. It is the lightest workable metal, only two-thirds the weight of aluminium, yet it has six times the stiffness of steel, making it an ideal mate­rial for stiffness-dependent and weight-limited applica­tions. The chart in Fig. 1 illustrates how much beryllium outclasses other engineering materials with respect to thermal conductivity and dimensional stability (ability of a material to retain its uniformity under stress measured as the Young's modulus to density ratio). These unique properties of beryllium translate into performance en­hancement in the end product, for instance the James Webb Space Telescope (JWST: see Fig. 2). The next gen­eration James Webb Space Telescope, scheduled to be launched in 2018 as NASA's replacement for the Hubble telescope, will utilise a 6.5 meter wide beryllium mirror to reveal images of distant galaxies 200 times beyond what has ever been sighted.