DavidForrest writes "The Foresight Conference this last weekend was one of the best ever. Kudos to all involved. I hate to nitpick after such a wonderful event, but as a metallurgist, I feel compelled to comment on the "metals are weak" meme that resurfaced several times. More… Metals are primarily weak because of defect structures that can be eliminated with molecular nanotechnology. Theoretical metal strengths can approach that of diamond, certainly within an order of magnitude. Although I quite agree that diamondoid materials will largely displace metals after we have molecular manufacturing, there will still be niches for metals: as oxides and intermetallics for high temperature applications, in applications where density or moment of inertia is a primary design consideration and strength is secondary, in certain kinds of radiation shielding, and in traditional handcrafts (yes, people will still be beating swords into shape at Renaissance faires after we have MNT). Oh, and by the way, guess which material has the highest stiffness (bulk modulus)? Diamond? Carbon nanotubes? Nope. Osmium, a metal. (http://focus.aps.org/v9/st16.html)
P.S.–Completely unrelated to strength, but fun trivia: the element in the periodic table that has the longest half-life is iron. So those of us who will still be around in 10**50 years or so may have mostly iron parts."