I had this constant nagging at the back of my head – why and how are the newly rolled out planes more fuel efficient, and not by a negligible margin?
Luckily asking around is still free, and the answer is “Ceramic Matrix Composites” allowing compression ratios of up to 60:1 and running 500 degrees hotter than current alloys, while at the same time being significantly lighter.
When will we see this kind of technology in a 400-1000 hp turbine for turboprops?
I guess never. It may well filter down to smaller turbojets…
The former CEO of MTU (one of the big airplane turbine makers) told me that we will probably never see a new turboprop design in the PT6 class. Developing such an engine for a market that small is financially not viable.
Everything we see today is designs from the 60s with new labels and small improvements.
what_next will probably know more about this, but what is called CMC is silicon carbide (aka carborundum) and it’s a very old composite material that even exists naturally in small quantities. Experiments with using it for gas turbines go back to the 1980s. It was originally used as an abrasive and to produce ballistic vests. The stuff used today goes back to developments of the University of Stuttgart and was first introduced in the mid 90s as ceramic brakes in Porsche cars and the last generation of the Space Shuttle heat shield. This is neither something revolutionary nor proprietary to GE…
It is also used in diesel particulate filters 
achimha wrote:
The former CEO of MTU (one of the big airplane turbine makers) told me that we will probably never see a new turboprop design in the PT6 class. Developing such an engine for a market that small is financially not viable.Everything we see today is designs from the 60s with new labels and small improvements.
Not entirely true. The new GE93 powering the Denali is quite a significant development of an older design.
