Replies to post #56087 on Tesla Inc (TSLA)

[boston745]

I do though. All 300 series steels are austenitic stainless steels that covert to martensite when cold worked and therefore magnetic. The fact that Musk said the material is akin to 304L means its properties will be the most similar to 304L. Besides its the same material used on the starship and therefore has to shield from EM radiation.

quote]Even though wrought austenitic stainless steels are non-magnetic in the annealed condition they may develop magnetic response when cold worked. Cold work can transform some austenite to martensite.

This has a dramatic effect on tensile strength and even more so on yield strength; a heavily cold drawn grade 304 wire can achieve a tensile strength of up to around 2000MPa. Such a highly worked 304 will also be very strongly attracted to a magnet.

Any process which can change the crystal structure of stainless steel can cause austenite to be converted to the ferromagnetic martensite or ferrite forms of iron. These processes include cold working and welding. It is also possible for austenite to spontaneously convert to martensite at low temperatures. To complicate matters further, the magnetic properties of these alloys depend on the alloy composition. Within the allowed ranges of variation of Ni and Cr, significant differences in magnetic properties may be observed for a given alloy.

“We’re rapidly changing alloy constituents and forming methods, so traditional names like 304L will become more of an approximation.”

A typical nuclear cask uses forged 304L stainless steel (SS) as an outer shielding layer
(0.75” thick) to attenuate gamma rays, and beech or spruce encased in 304L stainless steel shells
as impact limiter to absorb shock energy

This link shows how Teslas new exoskeleton material can help safeguard the electronics, wiring, & batteries from external magnetic induction.

https://www.kjmagnetics.com/images/blog/article2010.01.pic3p.gif

Quote # 1 Source
http://www.kimballphysics.com/media/images/MCF/magnetic_permeability.jpg

Quote #2 Source
https://www.greenwoodmagnetics.com/resource/what-is-the-difference-between-304-and-316-stainless-steel/

Quote #3 Source

We’re rapidly changing alloy constituents & forming methods, so traditional names like 304L will become more of an approximation

— Elon Musk (@elonmusk) July 21, 2020

Quote #4 Source
https://inis.iaea.org/collection/NCLCollectionStore/_Public/47/064/47064334.pdf