Super Steel

[Harold Squared]

The official website of L&S Electric, lselectric.com, reports that Korean metallurgy has produced a lightweight variety of steel which rivals titanium alloy in its strength per kilogram.

 

I am curious to find out more regarding this material, thanks in advance.

[StringJunky]

The official website of L&S Electric, lselectric.com, reports that Korean metallurgy has produced a lightweight variety of steel which rivals titanium alloy in its strength per kilogram.

 

I am curious to find out more regarding this material, thanks in advance.

The key to its properties are described thus but brttleness is a problem:

 

 

Scientists soon realized the problem: When creating the aluminum-steel alloy, they were occasionally fusing atoms of aluminum and iron together to form tough, crystalline structures called B2. These veins and nuggets of B2 were strong but brittle—until Kim and his colleges devised a solution.

 

"My original idea was that if I could somehow induce the formation of these B2 crystals, I might be able to disperse them in the steel," he says. The scientists calculated that if small B2 crystals were separated from one another, then the surrounding alloy would insulate them from splintering.

 

http://www.lselectric.com/new-super-steel-less-dense-strong-as-titanium/

[Harold Squared]

Thanks for the link. Steel is a notoriously tough material which is largely responsible for its usefulness.

[Enthalpy]

Any high-strength steel is better than titanium at equal mass.

 

Typical Maraging steel offers 2000MPa yield strength (some offer 2400MPa) for a density of 8030kg/m³ and isn't brittle at all. Compare with Ti-Al6V4: 830MPa and 4430kg/m³.

 

I'd love to use titanium more frequently, but it's not so exceptionally strong, and steel progresses more quickly than titanium does. A few alloys offer 1000 or 1200MPa but are really difficult to find, can't have thick sections, and other drawbacks.

 

Tensile strength versus density is not the whole picture. At parts resisting compression or bending, buckling often demands stronger sections than the yield strength would necessitate; to some extent, intricate hollow sections remedy this but they're more expensive and can't answer everything. Then, a lighter alloy is better than steel.

 

Problem is that aluminium alloys too are about as good (460MPa for 2820kg/m³) and are even lighter than titanium. Quite often, when steel is too dense, titanium doesn't fit neither, and aluminium is a better and cheaper solution. And of course, carbon fibre is a standard answer presently.