World-First Super Alloy Could Transform the Way Metals Are Made
World-First 'Super Alloy' Could Transform the Way Metals Are Made
We have developed a revolutionary method to create a super alloy by controlling atomic organization at lower temperatures. This Refractory High-Entropy Alloy is twice as strong as steel and three times stronger than aluminum, while retaining ductility. Our approach shifts focus from chemical composition to engineering internal structures, promising more sustainable and cost-effective metal production for industries ranging from aerospace to energy.
Instead of increasing alloy content to achieve better performance, we may be able to design internal structures that deliver superior properties with fewer alloying elements.
- rsfern
This is really cool metallurgy. They start with an alloy and deform it and because of elemental size mismatch they can cause the alloy to self assemble into nanoscale crystals with three different structures
The paper: https://www.science.org/doi/10.1126/science.aec4995
As an aside, “super alloy” is not the best wording choice on the part of the author of this sciencealert article, superalloys are an established alloy family that follow a different design strategy and have a very different composition profile https://en.wikipedia.org/wiki/Superalloy
- A_D_E_P_T
> Tests showed the new alloy achieved a compressive yield strength of more than two gigapascals while retaining its ductility, meaning it bends without breaking.
This is sleight-of-hand.
For metals, the operative properties are usually ultimate tensile strength and tensile yield strength. Compressive strength is typically a non-factor for most engineering alloys; only concrete is judged by its compressive strength, and sometimes various engineering ceramics. (e.g. SiC, compressive strength = 3.9 GPa.)
About ten years ago, there were a lot of papers on amorphous metal alloys that had "extreme strength" -- compressive strengths in the 5-6 GPa range -- but tensile strength was not reported and very low. Some measure of ductility was also present, but it too was very low. Those amorphous alloys were classical brittle materials; more ceramic-like than metal-like. I fear the same is probably the case here, with the alloy potentially fracturing along crystal type grain boundaries.
Until they report actual tensile strength and elongation, don't believe the hype. High compressive strengths are not very useful.
- htlemur_bobby
Hm I just read an article here recently that was saying that Americans had an edge in jet turbine blades production over china because Americans figured out how to make single crystal jet turbines using this same method. I wonder what the difference is.
- fwlr
Presumably, some initial information was fed into the start of this reporting process. Multiple stages of this process had near-total incomprehension of the information yet performed full ingestion and reconstitution of it anyway, leading to this terminally-confused output.
- iandanforth
"Steel is one of the classic alloy examples: mostly iron with a dash of carbon and other elements, making it much stronger and harder than iron on its own."
Statements like this had me confused for years about how steel is made. Steel is raw iron ore with some carbon removed. (Among other things) Pure iron isn't common in nature, it's usually found instead with too much carbon. That is, to have the properties we like in steel.