Like peeling lava off a metal block?
Inconel and Hastelloy aren’t THAT bad! We’ve been machining them, quite efficiently, since the early 50s, seriously since the early 60s. The X-15 (1959) was skinned with this stuff and many parts were made of this.
By-the-by, the X-15-2, the one that set the speed record (Mach 5.5), MELTED (Inconel) pylons off due to atmospheric friction! It was never flown again.
Yes, this is stuff that is a twitchy as it gets. Yes, the tooling has to be top notch… and you’re going to go through multiple tools even with top notch ones. Yes, the surface speed has to be tightly controlled. Yes, it is often machined by hand, rather than CNC. Yes, it gets hot… but you really want to avoid that since that causes much of the twitchiness.
IMHO, the reason these are often machined by hand, with constant adjustments, is due to the “magic formula” approach to feeds and speeds that most shops take. It is so twitchy, so unforgiving, and so far outside the experience level of most shops that mysticism is used. A human baby sitter constantly adjusts the machining.
With a solid understanding of the CNC equipment, tool selection, feeds and speeds and lubrication this is just another machining challenge. It is incredibly hard and machining is to some extent unbelievably slow… but it can be done and done well. Even with a CNC machine.
mark
P.S.
No, I’ve never machined it myself, but I have been around it and those who have machined it. Learning to machine it was the hard part. Once the lessons were learned, it was just another job… albeit expensive due to chewing up tools and the time it took.
P.P.S.
You want a creepy materials to machine?
Plutonium
It has 5 solid phases! The first two, as it heats up, expand. The third phase CONTRACTS! The next phases expand.
Many of the nasty accidents with it came from accidentally getting into the third phase and the resultant geometry took things from simple machining to a serious physics problem (Prompt Critical - not quite there but lots of neutrons and gamma rays).
Beryllium
The chips and dust are highly toxic. Nasty to the lungs. About 10% of the population will die, very quickly, from very small doses.
If you’re ever machining copper, please, please, please, make sure it is not an alloy containing Beryllium. You will not like the outcome.
By-the-by, the first one or two Mercury space capsule heat shields were solid Beryllium. They later switched to the composite stuff that ablates.