90+ exhaust manifold studs, inconel?

[Jussi Alanko]

Is that true that 90+ Volvo oem exhaust manifold studs are made from inconel?

I'm asking this, because i'm gonna change my turbos turbine housing to number 16#, turbo is a holset hx40 super.
And i'm not gonna put normal mild steel studs to turbine housing and dp:s flange, because, when i buy this turbo it is only driven for a 500km. Still the downpipes studs were totally corrosed and ill fight with them couple of days, actually i had to drill couple of them out.

With new turbine housing i'm gonna put studs that are not corrosive, so i can get them out when needed.

So volvos oem studs are perfect option if they are inconel?

[The]

I dont know if they are inconel, but I doubt it.
Most OEM uses copper nuts for exhaust to avoid seizing of the threads.

[Ersviken]

I have changed some turbos on 940 (96-98) and most of them has had rusty screws to turbo and downpipe.
So as "The" says, i also highly doubt inconel. my guess is 10.9 pinn-screws without surface treatment.