 In 2006, 77% of the rhenium consumption in the United States was in alloys.The rising demand for military jet engines and the constant supply made it necessary to develop superalloys with a lower rhenium content.For example, the newer CFM International CFM56 high-pressure turbine (HPT) blades will use Rene N515 with a rhenium content of 1.5% instead of Rene N5 with 3%.