Does there exist a metal that is 100% unrustable?

[LightningInAJar]

TL;DR

Unrusting metal?

Is there a metal that can never rust? I am tired of cars rusting even with antirust treatments.

 

[Vanadium 50]

Aluminum.

 

[Baluncore]

"Rust" or "Oxidize" or "Corrode" ?
Bronze is best in salt water.
Stainless steel is only stainless in the presence of oxygen.
Hot dip, or plate the parts in gold.

 

[nasu]

rust - a reddish- or yellowish-brown flaky coating of iron oxide that is formed on iron or steel by oxidation, especially in the presence of moisture. (from "Oxford Languages").

Any metal that is not iron or iron alloy is technically rust-free. You need to put more thought in what you actually want to ask.

 

[russ_watters]

Spray-painted polyethylene?

 

[jack action]

If we extend the definition of "rust" to "corrosion" or "oxidation", gold could be considered 100% unrustable:

Gold does not react with oxygen at any temperature and, up to 100 °C, is resistant to attack from ozone.

Platinum is a good contender also:

The metal has excellent resistance to corrosion, is stable at high temperatures and has stable electrical properties. Platinum does oxidize, forming PtO2, at 500 °C; this oxide can be easily removed thermally.

More info:

Intrinsic chemistry

Gold nuggets do not naturally corrode, even on a geological time scale.​

The materials most resistant to corrosion are those for which corrosion is thermodynamically unfavorable. Any corrosion products of gold or platinum tend to decompose spontaneously into pure metal, which is why these elements can be found in metallic form on Earth and have long been valued. More common "base" metals can only be protected by more temporary means.

Some metals have naturally slow reaction kinetics, even though their corrosion is thermodynamically favorable. These include such metals as zinc, magnesium, and cadmium. While corrosion of these metals is continuous and ongoing, it happens at an acceptably slow rate. An extreme example is graphite, which releases large amounts of energy upon oxidation, but has such slow kinetics that it is effectively immune to electrochemical corrosion under normal conditions.

Passivation

Passivation refers to the spontaneous formation of an ultrathin film of corrosion products, known as a passive film, on the metal's surface that act as a barrier to further oxidation. The chemical composition and microstructure of a passive film are different from the underlying metal. Typical passive film thickness on aluminium, stainless steels, and alloys is within 10 nanometers. The passive film is different from oxide layers that are formed upon heating and are in the micrometer thickness range – the passive film recovers if removed or damaged whereas the oxide layer does not. Passivation in natural environments such as air, water and soil at moderate pH is seen in such materials as aluminium, stainless steel, titanium, and silicon.

 

[berkeman]

Summary:: Unrusting metal?

Is there a metal that can never rust? I am tired of cars rusting even with antirust treatments.

https://www.popularmechanics.com/cars/a25938392/inside-delorean-motor-company/

 

[jack action]

Ford also explored the stainless steel avenue in 1936 (Tudor Deluxe Sedan) and again in 1960 (Thunderbird & Lincoln Continental):

The reason cars aren’t all made from stainless steel comes down to two (maybe three) factors. The first factor is that stainless steel is more expensive, the second factor is that it’s harder to work with and harder to weld, and the possible third factor is that it doesn’t rust which means cars would potentially last indefinitely. Clearly this would be less than ideal for the automotive industry, which relies on people buying new cars every few years.

Its resistance to corrosion, however, was what caught ol' Henry's attention in the late 1920s. A number of trim pieces on the Model A Ford, including the radiator shell, headlamp buckets and other various pieces of brightwork were made out of stainless steel; it replaced nickel-plating, which had proven to be not nearly as durable in the long term.

Sure enough, it wasn't long before Ford built three complete Model A bodies, including wheels, out of stainless; the bodies cost roughly $2,000 each--four times what a Model A cost to start with. Ford retained one example and two were given to a couple of steel companies as promotional tools; today, all have either been destroyed or have gone missing.

And so the 1936 Ford Tudor Deluxe sedan you see here, and the five others that were built alongside it, are not the first-of-their-kind harbingers of cutting-edge futurethink that many assume that they are. They did, however, manage to survive: Four of the six cars are still extant. Allegheny Ludlum, a steel company based in Pennsylvania, had them built by Ford as promotional tools, both to show off the wonders of stainless steel and as incentives for the sales department--free use of the car for a year if you were on top. But just because they lived long lives didn't mean they weren't a difficult birth: Pressing the body panels ruined Ford's tooling. The tools, dies and presses on the Ford line were designed to work with standard carbon steel, rather than high-chromium stainless, which is stronger and less flexible; some changes had to be made to the stamping dies, and welding various pieces together with the gas-welding technology of the day also posed a challenge.

[...]

As for the cars themselves, one went to each of Allegheny Ludlum's district offices in New York, Philadelphia, Cleveland, Detroit, Chicago and St. Louis. These were no trailer-queen promotional pieces shuttled to events. Oh, no, these were workhorses, each of them running for a purported 200,000 miles before they were retired from the Allegheny Ludlum fleet in 1946. They did their job, showing off the wonders of stainless steel to a public that automatically assumed that steel + water = rust, and convincing them to approach the material with an open mind. After a decade on the road, the bodies still looked great, but the drivelines were well-worn; they were standard-issue Ford pieces after all, used 20,000 miles a year for a solid decade.

 

[DaveE]

I am tired of cars rusting even with antirust treatments.

Move to Tucson?

 

[LightningInAJar]

Lets assume can't rust, corrode, or oxidize. I realize it would likely increase the cost of the car, but the body of the car isn't the most expensive part? Personally kind of wish there were more separate panels that weren't large pieces so the body could be replaced like the planks of a boat that may or may not remain the same boat. Lol. Aren't rusting cars essentially littering themselves all over the road? So pretty much anything with iron will rust?

 

[berkeman]

Lets assume can't rust, corrode, or oxidize.

Which parts of the replies from Jack and myself did you not understand?

 

[nasu]

But the body of the car is more and more made from aluminum or even non-metallic composites. There are even pistons and engine blocks made from aluminum. I wish I had a car with steel body and a bumper that does not crack when I hit a hard pile of snow. Or maybe not. A crumpling body has the advantage of protecting the passengers.