Do metals get old and weakened through time?

Pattree

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Jul 19, 2023
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I have an old steel handled shovel, left behind by some guys laying the Mercury cable many years ago. If I leave that out in rain I have to remember to turn it upside down and thoroughly drain the handle and then dry it after a load of rusty brown water has flowed out. It will doubtless corrode through one day but I’m guessing it will see me out.
 

Laurentius

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Aug 13, 2009
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Depends on whether the steel comes from China or not, I am absolutely horrified at what we are about to lose at Port Talbot.
 
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Laurentius

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Yes, it’s called metal fatigue, and it’s use rather than time. The same effect as the hardening of a bit of steel wire when bent back and forth. It hardens and snaps.
It used to be the case that the handle went way before the blade, I never had a blade snap on me until fairly recently and I have to conclude that it is the usual suspects, quality steel having gone back at least 500 years in the last decade or two.
 

Paul_B

Bushcrafter through and through
Jul 14, 2008
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Operator error obviously!

We had an engineer at work whose opinion on everything that went wrong was operator error. It wasn't, more likely someone bodging the repair job in the first place. It did become a running joke and that ended up peeing him off even more when he had to go back to patch up his own shoddy work for the nth time.
 

spader

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Dec 19, 2009
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It was strange to see the spade had little rust inside the cavity where it joins the handle, and it broke off.

I have another old spade probably military issued one from 1940s. It is 50 times more rusty all over the blade, also around the whole metal part, and it still is robust and solid. Even the wooden handle is original, and has no structural issues. It is heavier than the broken spade, and works as it did same as probably in 1940s (although I wasn't around at the time, I am certain that is the case).
 

Kadushu

If Carlsberg made grumpy people...
Jul 29, 2014
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I've had (=eventually broken) several stainless steel spades over the years. I recall the last one had a similar fracture to the OP's. Evidently there had been an invisible crack for some time which had corroded. Bear in mind that polished steel will not rust as readily as rough/grainy steel and the exterior surface will dry more easily than inside a crack. The stainless steel used for spades does seem to be on the brittle side.
 

Pattree

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Poorly made stainless steel can contain contaminants that create weak spots and micro cracks. Once water gets in there it forms an electric cell and starts a process called bimetallic corrosion. This could create the rust on the face of the crack in your spade.

Anyone who owned a BMC car in the seventies knows all about bimetallic corrosion. The chromed steel strips along the sides of my Wolesly were held onto the thin steel panels by aluminium rivets. It developed circles of rust around each rivet.

That may well have been happening in your spade. That said: in terms of days use per £ spent it wasn’t a bad deal and hey, you had a backup :)
 
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Laurentius

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Anyone who owned a BMC car in the seventies knows all about bimetallic corrosion. The chromed steel strips along the sides of my Wolesly were held onto the thin steel panels by aluminium rivets. It developed circles of rust around each rivet.
Anyone who has ever had a classic Land Rover will know all about that.
 

Pattree

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Anyone who has ever had a classic Land Rover will know all about that.
Who’s had a replacement bulkhead fitted then? A series 3 owner once described how rainwater was channeled from the windscreen down to the junction between the Burmabright wings and the mild steel bulkhead. He swore it was deliberate.

The spade will probably have been made with a life expectancy. Folk of my age have usually accumulated two or three generations of tools. I may well pass them on but some of my more recent stuff won’t go far down the line.
 

spader

Native
Dec 19, 2009
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In the past I have been under the impression that stainless steel or alloy steel would be stronger and tougher than carbon steel, but was surprised to witness that is not the case.

In the book, Stainless steel should be less prone to rust, but it doesn't seem to be the case either.
 

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