zlacker

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1. wahern+(OP)[view] [source] 2021-05-25 22:39:57
> The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless

Even stainless steel rusts, just more slowly. Roughly 10-100x more slowly, judging by https://www.nrc.gov/docs/ML1124/ML112490377.pdf and https://www.mdpi.com/2076-3417/10/23/8705/pdf.

replies(4): >>petera+w5 >>mrfusi+sn >>strken+Lq >>brutus+gw1
2. petera+w5[view] [source] 2021-05-25 23:15:47
>>wahern+(OP)
That doesn't smell right. I've got 15 year old knives that have never once shown signs of rust. A pair of old scissors left in the rain rusted in under a day. That puts the factor to closer to >10000 than 10 or 100...
replies(4): >>soperj+B6 >>sgille+Q6 >>mardif+W6 >>_jal+oh
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3. soperj+B6[view] [source] [discussion] 2021-05-25 23:23:53
>>petera+w5
You leave your knives outside?
replies(1): >>phkahl+d7
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4. sgille+Q6[view] [source] [discussion] 2021-05-25 23:24:59
>>petera+w5
Maybe if you want to invalidate those studies you can try leaving the knives out in the rain 10-100 days in a row!
replies(2): >>dylan6+kd >>petera+5w1
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5. mardif+W6[view] [source] [discussion] 2021-05-25 23:25:51
>>petera+w5
There are different grades of stainless steels. The common, "construction" grade stainless steels usually rust albeit very slowly. And while some of them are basically impervious to corrosion, they are usually way more expensive or have a lot less tensile strength. I don't know about knives specifically but it wouldn't surprise me if those more corrosion resistant grades are what's used to make them.
replies(2): >>LoveMo+rd >>brandm+df
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6. phkahl+d7[view] [source] [discussion] 2021-05-25 23:27:13
>>soperj+B6
Knives tend to get washed.
replies(1): >>froste+S7
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7. froste+S7[view] [source] [discussion] 2021-05-25 23:31:44
>>phkahl+d7
And immediately dried.
replies(1): >>thisis+Rp
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8. dylan6+kd[view] [source] [discussion] 2021-05-26 00:09:21
>>sgille+Q6
Only if you live in a rain forest.
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9. LoveMo+rd[view] [source] [discussion] 2021-05-26 00:10:33
>>mardif+W6
All correct. Stainless steel is 'created' by adding chrome and a few other materials depending on the desired properties. But despite that it will still rust.

I think a good analogy world be eating healthy, you'll probably live longer then soon-to-be who doesn't eat healthy but in the end both will die and seize to exist.

Material science is incredibly interesting field and I think it will play a huge role in the future. It already does.

replies(1): >>sokolo+Hl
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10. brandm+df[view] [source] [discussion] 2021-05-26 00:26:38
>>mardif+W6
Example: The Gateway Arch was surfaced with a stainless steel alloy, and it is suffering some corrosion problems today.
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11. _jal+oh[view] [source] [discussion] 2021-05-26 00:46:11
>>petera+w5
There are different grades of steel, doped with all sorts of additives, depending on the desired traits. The most corrosion-resistant variant today used in knives would be one of the nitrogen steels, like Nitro-V.

https://knifesteelnerds.com/2019/09/23/nitro-v-its-propertie...

But they all corrode, eventually. If you want a true corrosion-resistant metal that stays (kinda) sharp, look at one of the cobalt alloys like Stellite.

replies(1): >>AceyMa+Sw
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12. sokolo+Hl[view] [source] [discussion] 2021-05-26 01:21:59
>>LoveMo+rd
Word tip: “cease to exist” rather than “seize”
replies(1): >>LoveMo+wF3
13. mrfusi+sn[view] [source] 2021-05-26 01:38:04
>>wahern+(OP)
What are car mufflers made of that they resist rust so well?
replies(3): >>naikro+Gq >>zelon8+hv >>sjg007+Y55
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14. thisis+Rp[view] [source] [discussion] 2021-05-26 01:58:44
>>froste+S7
My knives started showing some rust spots. I thought there must be something wrong with the knives, but I realized after googling, it was something wrong with how I was washing the knifes... I left it in a tub of very hot water and soap for a day, did this multiple times, viola, rust spots.
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15. naikro+Gq[view] [source] [discussion] 2021-05-26 02:07:41
>>mrfusi+sn
plain steel, I believe, but they get very hot on trips of even a few km, which drives off any resting moisture and prevents exhaust moisture from condensing for a while after the engine is stopped.

cars that make many short trips, which never give the exhaust system time to fully warm up, often have extremely compromised exhaust systems, because the moisture simply can't be driven away effectively.

replies(1): >>mrfusi+ss
16. strken+Lq[view] [source] 2021-05-26 02:08:38
>>wahern+(OP)
I went and googled the most obvious solutions I could think of for protecting rebar from rust.

- dipping rebar in epoxy is sometimes done, but a single nick in the coating causes all the erosion to concentrate in that one spot, so it can be more dangerous than just uncoated rebar

- galvanised rebar works much better than epoxy, and resists corrosion at lower pH levels than normal iron, but may result in more metal loss under some conditions

- sacrificial anodes (as per the article) can and are used, but exactly how is quite complicated: if they're embedded in the concrete, the zinc breaks down into substances that can weaken it

- concrete is naturally alkaline, with cement being manufactured partly from lime, and this protects the rebar, but too high a pH causes other problems in the concrete itself, so you can't just dump alkaline substances into the mixture forever

- you can apparently use fibreglass as rebar, but I have no idea if it's any good, or what happens to fibreglass if you leave it embedded in concrete for a century

replies(1): >>sjg007+G55
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17. mrfusi+ss[view] [source] [discussion] 2021-05-26 02:23:33
>>naikro+Gq
Still crazy to think they drive through salted roads for a decade and are basically ok.

Btw were Deloreans pretty rust resistant? How will the cyber truck do living by the beach?

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18. zelon8+hv[view] [source] [discussion] 2021-05-26 02:49:26
>>mrfusi+sn
You must not live in New England.
replies(1): >>slenk+SN
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19. AceyMa+Sw[view] [source] [discussion] 2021-05-26 03:03:16
>>_jal+oh
You may like SPY27 if cobalt is what you seek. (=> new steel which just dropped <small_value> weeks ago.)

/Acey

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20. slenk+SN[view] [source] [discussion] 2021-05-26 05:34:13
>>zelon8+hv
Anywhere with regular snow*
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21. petera+5w1[view] [source] [discussion] 2021-05-26 12:16:08
>>sgille+Q6
In fact we lost the kitchen shears from the set for half a year, no rust.
22. brutus+gw1[view] [source] 2021-05-26 12:17:12
>>wahern+(OP)
You are correct for certain definitions of 'stainless steel.' However as other comments have alluded to, some grades of 'stainless steel' will rust so slowly that they will survive orders of magnitude longer than recorded history. For example, some "Hyper-duplex" stainless steels are designed to resist corrosion in seawater that is above boiling point. This steel is probably not economical for building construction, but if you wanted it to last for millenia, it may be the optimal choice.
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23. LoveMo+wF3[view] [source] [discussion] 2021-05-27 00:12:01
>>sokolo+Hl
Now that you said it, it totally makes sense, because too seize, means to take away as in: The police seized my laptop. Thanks ^^
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24. sjg007+G55[view] [source] [discussion] 2021-05-27 14:02:17
>>strken+Lq
If you can use fiberglass as rebar then maybe we could reuse/remanufacture wind turbine blades as rebar.
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25. sjg007+Y55[view] [source] [discussion] 2021-05-27 14:03:30
>>mrfusi+sn
I'm not sure if you are being sarcastic but mufflers rust quite a bit.
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