See: Ryusuke Hasegawa: "Glassy metals: magnetic, chemical and structural
properties". CRC Press, 1983, 280pp.
p. 189: "Characteristic values (of the elastic limit) for Fe-Ni and
Co-based metallic glasses range from 2000 to 2500 N/mmsq. Typical values
of Young's modulus are 150 kN/mmsq for the same group of alloys. This
means that they can be subjected to four to five times the stresses and
elastic strains that can be sustained by crystalline Fe-Ni-based soft
magnetic materials without plastic deformation and have correspondingly
2000 to 2500 MPa UTS ist strong. But if they don't show sufficient
elongation to failure, their use for structural applications is limited.
For gas turbines, creep-resistance is necessary.
A relatively low modulus of 150 GPa is useful for
If the material ist compared to "Fe-Ni-based soft magnetic materials",
it is probably not aimed as a structural material.
Amorphous materials are made when they're cooled too quickly for the atoms
to arrange themselves into crystals. Raising the temperature increases
the mobility of the atoms. If you use it in high temperature
applications, it won't stay amorphous very long.
"Don't try to teach a pig how to sing. You'll waste your time and annoy
Speaking of turbines, since you bring it up, thermal barrier coatings are
used on turbines to increase their operating temperature. But one thing
I'm not clear on is that when it's running for a while, TBC or not, those
blades are going to heat up anyway unless they're continually shedding
heat. How do they do that? Conduction through the blades to a cooled
"Then they placed the ark of the Lord on the cart; along with the box
containing the golden mice and the images of the hemorrhoids."
Common knowledge for heat engines..... seeking the highest operating
temperature for maximum extraction of work from a given amount of fuel.
It helps to remember thermodynamics, sometimes. Understanding is quite
email@example.com (Gregory L. Hansen) in
Kerosene by now must be 80 - 85% of the cost
of air travel.
A 50 MW aircraft engine is pretty cheap on a
dollar/hp basis as well as on a engine cost/
fuel cost basis.
Some NASA engineer said 60% of the R & D
cost of gas turbines was materials.
That seems to be a tradition. No overview of how this thermal barrier
coating stuff works in a system, and it is probably assumed that anybody
interested in these barrier coatings already knows why and how they work.
Remembering back to my first exposure to the field. They make little
sense until their role in cooling is explained. So, there is a long
tradition of this.
Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here.
All logos and trade names are the property of their respective owners.