Can’t help with id of it’s type - but don’t be surprised to find multiple metals - pure one metal frames are few and far between. Often they aren’t found on factory bikes unless they’ve sourced a wholesale supply of specialist build frames built to an OEM spec.
Where you do get factory built cycles with pure build frames, it’s usually the first series (usually short production) using hi grade specialist sourced frames, later production/series use reduced cost less pure single metal frames.
But there are often mixed sections especially around join sections that aren’t one metal due to rigidity/resilience workaround choices.
Try actually designing, and doing the obligatory FEA simulation runs to determine the rigidity and actual stress factors, and you rapidly understand why sometimes the end result of a production frame is less than as pure as the concept.
Believe or not, just building or designing based on theory or baseline designs can equally create an unfit for purpose design even if it’s technically (by theory) bombproof strong.
Just thought it was worth mentioning since the dark magic and sorcery of construction rarely gets mentioned.