The Tesla Cybertruck is indeed still in development. While news on the thing is sparse, especially the release date, there’s scattered news about it, such as seeing the prototype with mirrors and a massive central windshield wiper in 2021. The latest: Tesla has filed a patent application for a steel alloy that will encase the exoskeleton of the cyber truck.
According to electric draft, the steel should outperform other typical automotive grade alloys. In the patent application, Tesla outlines fairly detailed specifications about the Vicker hardness scale, corrosion resistance, ductility and tensile strength. For the nerds, it will range from 420 HV to 500 HV on hardness, have 520 mV to 600 mV corrosion resistance, a ductility of 60 degrees bend angle at 1.8 mm thickness and a yield strength of 1100 MPa.
Tesla listed a few other common steel alloys in the filing, including the common 304L, 316L, and 301. Apparently none of these could meet the specifications Tesla requested for the Cybertruck, which will reportedly use a unique chassis body structure with a exoskeleton draped over it for added durability. This exoskeleton could be made with the proprietary alloy described in the patent.
The automaker doesn’t explicitly say it will use the alloy on the Cybertruck in the patent, but does note that it could be used in an exoskeleton vehicle. It also appears that corrosion resistance is a major concern of this alloy, with the patent application stating that “in some embodiments, the corrosion resistance of the monolithic metal plate allows the exterior panel of the vehicle to be used without applying an anti-corrosion coating.” or corrosion protection agent (e.g. paint).”
Reading between the lines, the “30X” shouldn’t mean 30 times more, rather it resembles a nomenclature used for 300 series stainless steels that can only be hardened by cold rolling. So this is likely going to be a mix or variation of 300 series stainless steel, which is not that uncommon in the industry.
Whether it will be used on Cybertruck remains to be seen. The next Tesla Investor Day is just around the corner and details will surely be released then.