Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

Lots of old lightweight materials show tensile strength greater than steel.

For instance, oh, nylon fiber is stronger than some steels, and way less dense:

https://en.wikipedia.org/wiki/Ultimate_tensile_strength#Typi...

One kind of steel, "ASTM steel" comes in at 400-500 MPa; nylon fibers at 900.

Check out the Bamboo entry in the table. Human hair is also impressive.



BIS80 is a structural steel who's formula is owned by Bisalloy and produced under license by steel manufacturers.

BIS80 has a yield strength in excess of 620 Mpa, and an ultimate tensile strength in the range 720 to 930 Mpa.

See here for more info https://www.bisalloy.com.au/wp-content/uploads/2020/06/BISAL...

BIS100 has a yield strength around the 890 MPa mark, and an ultimate tensile strength in the range 940 to 1100 MPa.

See here for more info https://www.bisalloy.com.au/wp-content/uploads/2020/06/BISAL...

Nylon is lighter, but it also loses about 20% of its tensile strength when wet.


FWIW, that Wikipedia table lists several steels which have a much higher ultimate tensile strength.


I see that now I've opened it ;)

I'm familiar with the Bisalloy steels because I have them here right in front of me (metal fabricator by trade and laser cutter operator past 8 years).


Yep. This is a very interesting material, and of course it's a research prototype -- but it's not very strong. They list the modulus as 12.7 GPa and the yield strength (= ultimate tensile strength, since the film tears) as 488 MPa.

In comparison, polyimide (PMDA-PPD), which also easily solvent processable, has a modulus of 8.9 GPa, and a yield strength of 350 MPa.

Less equal comparisons involve polymers that are molecuarly aligned by drawing, spinning, or chemical processes. Dyneema UHMEPE has a modulus of 110 GPa and a ultimate tensile strength of 3.5 GPa. Kevlar is similar; it utilizes interlocking hydrogen bonds to convey strength. Even stronger are glass fibers (>4 GPa tensile strength) or PAN carbon fiber (> 6 GPa tensile strength).

You of course lose some strength when you make composites out of fiber -- but irregardless this polymer is many times weaker and softer.




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: