News
SpaceX to use superalloys in Mars rocket Raptor engines, says Elon Musk
A few days after he touched upon methods of creating BFR propellant on Mars, SpaceX CEO Elon Musk mentioned in a tweet that the launch company was using cutting-edge combinations of metals (known as superalloys) to ensure the efficiency and reliability of its Raptor rocket engine, a critical requirement for BFR to enable sustainable colonization of Mars.
In response to a tweeted question about types of metal alloys currently in use at SpaceX, Musk briefly delved into the complexities of building BFR’s propulsion system, particularly with respect to alloys capable of surviving the intense conditions inside a rocket engine:
“[SpaceX is using] SX 300 & soon SX 500. Kind of a modern version of Inconel superalloys. High strength at temperature, extreme oxidation resistance. Needed for ~800 atmosphere, hot, oxygen-rich turbopump on Raptor rocket engine.” – Elon Musk
There’s a lot to break down for the layperson in Musk’s tweet. First and foremost, commenters (your author included) immediately jumped to the conclusion that “SX 300/500” referred to some sort custom SpaceX material, given that SX is a frequent shorthand for SpaceX used in the enthusiast community. In reality, it was quickly discovered that the requirements Musk described for the material – namely “high strength at temperature [&] extreme oxidation resistance” – were nearly the exact same qualities of single-crystal superalloys, extremely advanced metal formulations also notated as SC or SX. It’s quite the apt coincidence that SpaceX will apparently rely on SX alloys for critical components of BFR propulsion.
A 2017 test-firing of the mature development Raptor, roughly 50% less powerful than the full-scale system. (SpaceX)
Single-crystal superalloys employ small amounts of exotic elements in order to better ensure truly unusual crystal formation in metal structures. In the case of SX alloys, the optimal result is a monolithic metal structure that effectively has no visible grain (think wood grain but in metal) – the resulting metal would be a huge monolithic crystal, in other words, uniform down to a near-atomic level. These SX superalloys are already used regularly for industrial applications requiring the ability to reliably operate in extremely corrosive high-pressure, high-temperature environments for long periods of time, most frequently seen in gas turbines for energy generation and airplane propulsion.
Per Musk, SpaceX intends to take those alloys a step further, developing its own SX-300 and SX-500 iterations for the purpose of building a reliable, robust turbopump for the Raptor propulsion system. In pursuit of the greatest possible efficiency, Raptor’s turbopump will run oxygen-rich, meaning that the inherently imperfect combustion process will lean towards excess oxygen in the exhaust, rather than excess methane. In simple terms, this choice is partially motivated by the fact that oxygen molecules are slightly lighter than methane molecules (15.999u vs. 16.04u). More importantly, the higher the pressure in the turbopump, the higher the pressure in Raptor’s combustion chamber, which directly correlates with more efficient combustion and thus a more efficient rocket engine overall. All improvements to its subcomponents will inherently end up benefiting SpaceX’s BFR booster and spaceship, the latter of which is already nearing initial prototype construction.
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- SpaceX’s current Texas facilities feature a test stand for Raptor, the engine intended to power BFR and BFS to Mars. (SpaceX)
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- SpaceX’s Raptor proceeds through the complex process of ignition. (SpaceX)
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- SpaceX’s subscale Raptor engine has completed more than 1200 seconds of testing in less than two years. (SpaceX)
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- SpaceX’s three-bay Raptor test stand as of April 17. The middle bay is currently home to the subscale Raptor test program. (Aero Photo)
While SpaceX cut its original Raptor specifications by roughly 50% compared to its 2016 goals, it appears that the company’s ambitions for the downsized Raptor are smaller in name only. In a May 2018 presentation, Chief of Propulsion Tom Mueller foreshadowed those future ambitions while humbly acknowledging that the Merlin 1D powering Falcon 9 and Heavy is already a masterpiece of engineering: “Merlin holds the thrust to weight record for now… but Raptor’s coming.”
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Elon Musk
Elon Musk teases massive new Tesla-xAI joint project known as ‘Digital Optimus’
It is the latest move by a Musk company to automate, streamline, and reduce the manual, monotonous, and tedious work currently performed by humans through AI and robotics development. Digital Optimus will be capable of processing and actioning the past five seconds of a real-time computer screen video and keyboard and mouse actions.
Elon Musk teased a massive new project, to be developed jointly by Tesla and xAI, called “Digital Optimus” or “Macrohard,” the first development under Tesla’s investment agreement with xAI.
Musk announced on X that Digital Optimus will “be capable of emulating the function of entire companies.”
Macrohard or Digital Optimus is a joint xAI-Tesla project, coming as part of Tesla’s investment agreement with xAI.
Grok is the master conductor/navigator with deep understanding of the world to direct digital Optimus, which is processing and actioning the past 5 secs of…
— Elon Musk (@elonmusk) March 11, 2026
It is the latest move by a Musk company to automate, streamline, and reduce the manual, monotonous, and tedious work currently performed by humans through AI and robotics development. Digital Optimus will be capable of processing and actioning the past five seconds of a real-time computer screen video and keyboard and mouse actions.
Essentially, it will be an AI version of a desk worker in many capacities, including accounting, HR tasks, and others.
Musk said:
“Grok is the master conductor/navigator with deep understanding of the world to direct digital Optimus, which is processing and actioning the past 5 secs of real-time computer screen video and keyboard/mouse actions. Grok is like a much more advanced and sophisticated version of turn-by-turn navigation software. You can think of it as Digital Optimus AI being System 1 (instinctive part of the mind) and Grok being System 2. (thinking part of the mind).”
Its key applications would be used for enterprise automation, simulating entire companies, high-volume repetitive tasks, and potentially, future hybrid use with the Optimus robot, which would handle physical tasks, while Digital Optimus would handle the clerical work.
The creation of a digital AI suite like Digital Optimus would help companies save time and money, as well as become more efficient in their operations through massive scalability. However, there will undoubtedly be concerns from people who are skeptical of a fully-integrated AI workhorse like this one.
From an energy consumption perspective and just a general concern for the human workforce, these types of AI projects are polarizing in nature.
However, Digital Optimus would be a great digital counterpart to Tesla’s physical Optimus robot, as it would be a hyper-efficient addition to any company that is looking for more production for less cost.
Musk maintains that there is no other company on Earth that will be able to do this.
Elon Musk
Tesla China posts strong February wholesale growth at Gigafactory Shanghai
The update was shared by Tesla observers on social media platform X, citing monthly China Passenger Car Association (CPCA) data.
Tesla China sold 58,599 vehicles wholesale in February, reflecting strong year-over-year growth. The figure includes both domestic deliveries in China and vehicles exported to international markets.
The update was shared by Tesla observers on social media platform X, citing monthly China Passenger Car Association (CPCA) data.
Tesla’s February wholesale result represents a 91% increase year over year, compared with 30,688 vehicles in February 2025. Month over month, the result was down 15.2% from January, when Tesla China recorded 69,129 wholesale units.
The February total reflects combined sales of the Model 3 and Model Y produced at Gigafactory Shanghai. The facility produces the two vehicles for both domestic sales and exports.
Gigafactory Shanghai continues to serve as Tesla’s primary vehicle export hub, supplying vehicles to markets across Asia and Europe. Data compiled by Tesla watchers shows that 18,485 vehicles were sold domestically in China in January 2026, while exports accounted for 50,644 units during the same period.
Tesla has also been extending financing programs in China as it pushes to strengthen domestic demand. The company recently extended its seven-year ultra-low-interest and five-year interest-free financing programs through March 31, marking the second extension of the promotion this year.
The financing initiative was first introduced on January 6 as a strategy aimed at offsetting higher ownership costs ahead of China’s planned 5% NEV purchase tax in 2026. The promotion was originally scheduled to expire at the end of January before being extended to February and then again through the end of the first quarter.
Tesla’s efforts come amid growing competition in China’s EV market. According to data compiled by CNEV Post, Tesla’s 2025 retail sales in China reached 625,698 vehicles, representing a 4.78% year-over-year decline. Part of that decline was linked to the Model Y changeover to its updated variant in early 2025, which temporarily reduced deliveries during the transition period.
News
Tesla Model Y L spotted on transport trucks in Australia
One of the sightings was reported along Victoria Parade in Melbourne, and it showed multiple Model Y L vehicles on a transport carrier.
Tesla’s upcoming Model Y L has been spotted on transport trucks in Australia. Sightings of the six-seat extended wheelbase Model Y variant have been reported on social media platform X by members of the Australian Tesla community.
One of the sightings was reported along Victoria Parade in Melbourne, and it showed multiple Model Y L vehicles on a transport carrier.
The sighting follows earlier observations by Tesla enthusiasts in Sydney, where a covered vehicle believed to be a Model Y L was spotted at a Supercharger.
The Sydney sighting drew attention after observers noted that the vehicle’s tare weight appeared to match the ADR approval listing for the Model Y L, suggesting it could indeed be the extended wheelbase variant of the electric SUV.
Tesla has previously confirmed that the Model Y L will launch in Australia and New Zealand in 2026. The confirmation was reported by techAU following a media release from Tesla Australia and New Zealand.
The Model Y L expands the existing Model Y lineup with seating for six passengers. The vehicle features a longer body compared with the standard Model Y in order to accommodate a spacious second and third row.
Tesla has opted for a 2-2-2 seating configuration instead of a traditional seven-seat layout for the Model Y L. The design includes two individual seats in the middle row to provide easier access to the third row and additional passenger space.
Tesla Australia and New Zealand has also stated that the Model Y L will be covered under the company’s updated warranty structure beginning in 2026.
Tesla has not yet announced pricing or official range figures for the Model Y L in Australia.
Elon Musk teases massive new Tesla-xAI joint project known as ‘Digital Optimus’
Tesla China posts strong February wholesale growth at Gigafactory Shanghai
