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This comes from a slightly related question about blisks. A blisk is a single component shaped like a disc with blades on it. This can be for compressors or turbines.

I want to ask about the turbine possibility here. Are turbine blisks common on relatively new jet engines, either commericial or military? It's arbitrary, but take "relatively new" to mean designs that went into production within the last 10 years, maybe give or take a few years.

The turbine has the most difficult alloy, superalloys, so I am wondering if blisk manufacture is made more difficult because of this or is infeasible for some reason. (Note the blisk has several disadvantages, like if one blade is damaged the entire blisk needs to be taken out and repaired/replaced, but that alone doesn't suggest to me why turbines would be more problematic than compressors.)

Just for reference, the first turbine stage needs to handle temperatures of 1700 to 1800 K.

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To my knowledge, there are no turbine blisks in any current engine. There may be one out there I don't know about, but they certainly are not common.

The reason is blade life. With a blisk, if you have to replace one blade, you have to replace the entire blisk. Repairs due exist, of course, but if it is too badly damaged to be repaired you have to replace everything. With separate blades, you can replace only the ones that need to be replaced.

Turbine blade life is much shorter than compressor blade life, due to the extreme temperature environment. A typical engine might go through multiple entire sets of turbine blades in its lifetime. An average compressor blade might last the entire lifetime of the engine.

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    $\begingroup$ You answer was nearly 5 hours after the question. Next time, be more blisk about it. If you can touch type like me, you can type very bliskly, improving matters further. $\endgroup$
    – John K
    Commented Sep 8, 2021 at 22:13
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    $\begingroup$ @JohnK That's just bliskful thinking. $\endgroup$
    – Sanchises
    Commented Sep 9, 2021 at 9:24
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I'm in aircraft engineering school right now, and i can tell you blisks are definitely in use.

For example the Rolls-Royce Trent 500 turbofan, or the Allison Model 250.

(The latter of which we have a cut-open version of, on a dolly here)

This is the turbine section as blisk (edit: corrected from fan)

Turbine stages

And this is the compressor stages as blisk vvv

Compressor stages

If you have any questions, i'll be glad to elaboate. :)

Edit: I saw you wanted more recent engines!

The Hf-120 turbofan, first run in 2009 utilizes blisk technology

enter image description here

Edit 2:

Even more recent is the R-R Trent XWB, with new blisk drums. Certified in 2013

RR XWB

Oberusel factory reached a milestone of shipping out 10.000 blisks in 2019, for this engine

(europawire.eu)

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  • $\begingroup$ Oh, also the The Eurojet EJ200 engine. And I just realised you wanted an answer about engines within 10 years ;_; $\endgroup$
    – Noddle
    Commented Sep 29, 2021 at 6:02
  • $\begingroup$ Thank you but my OP explicitly says turbine blisks, not compressor blisks or fan blisks. $\endgroup$
    – DrZ214
    Commented Sep 29, 2021 at 7:22
  • $\begingroup$ Sorry, that's a mis-definition by me, the first picture is a blisk turbine (on the Trent 500) $\endgroup$
    – Noddle
    Commented Sep 29, 2021 at 7:47
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    $\begingroup$ Give me a little time, i'll pass the question by my professors $\endgroup$
    – Noddle
    Commented Sep 29, 2021 at 8:01

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