The ideal sandpaper for hard metals like iron or steel is aluminum oxide, whilst the top sandpaper for softer metals for example aluminum or brass is silicon carbide. Carbide LED output quickly stopped when another material, gallium nitride, showed ten–a hundred periods brighter emission. This difference in efficiency is due https://www.facebook.com/permalink.php?story_fbid=pfbid0svDBUCHiMbbC3LbXyqGEvPhVLMA4F4cPNj72CvJGFYFYG2LijyzGtZxkw5YoHaAZl&id=61562415773754&__cft__[0]=AZXjXxNpXP9OY21CplUGaT3HrcGGcBp--ol-v_va0RicPyjD4GGxkUz9jYILuQXHOxGhcWWBgKUnkiwClJ3Eu9QOMQZnDuhsWCs-9_3opxCtCDIUZJndvCy76zVHwOp7QmmgEORmLL-RWtV_VFWb4LrYNUX_O2Lg_OSPdwDAqyOCI_ZBQTQIt9MZ9hm1Nqw-eyPMGYCW4mMNpsGNn7w_KA6C&__tn__=%2CO%2CP-R