Phase equilibria in the system vanadium oxide-niobium oxide

Tbe p ha se diagram for the pseudo-binary system 1'20 5--Kb20 S was co nstructed from fusion c haracte ristics a n d x-ray diffraction . data. Three co mpounds wer.e postulated for thc system . The compo un d YNb,025 an d Y2 ~b 23 0 G2 \\'erc found to melt lIl co ngruently at a bout 1290 C and 1322 C respectivcly. The t hird compound OccU LT ing at about 93 to 94 mole p crcen t ~b205 m cl kd in con~ruentl y at approximately 13:32, ac . . Apparcn tly, Nb 20; accep ted up to .~ mole p ercent \ 205 JI1 solid SOlu t lOll , howeve r, \ 20 5 (lId n ot accept any appreciable ~b 20, in solid sol ution.