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MIT STUDY ON THE REASON WHY HAIR DAMAGES RAZORS

Interesting article by MIT. Don't know if this has been posted yet or not. Down below, I pasted some excerpts from the article that I found interesting on what causes shaves to get dull. Do the results surprise you or does it verify what you already knew? I know about homogenous super steels for knives and the benefits for them, but I'm not really familiar in detail about razor steels and how homogenous they are, and that seems to be a pretty important factor in dulling. And the angle of attack, I know there are some differing preferences of the angle of attack when it comes to shaving, but knowing this information is a bit enlightening and something I may keep in mind when practicing my shaves as well. Thoughts?

Why shaving dulls even the sharpest of razors - https://news.mit.edu/2020/why-shaving-dulls-razors-0806
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"he found that chips did not occur when the hair was cut perpendicular to the blade. When the hair was free to bend, however, chips were more likely to occur. These chips most commonly formed in places where the blade edge met the sides of the hair strands."

"They found that the simulations predicted failure under three conditions: when the blade approached the hair at an angle, when the blade’s steel was heterogenous in composition, and when the edge of a hair strand met the blade at a weak point in its heterogenous structure."

“Our simulations explain how heterogeneity in a material can increase the stress on that material, so that a crack can grow, even though the stress is imposed by a soft material like hair,” Tasan says."

The researchers have filed a provisional patent on a process to manipulate steel into a more homogenous form, in order to make longer-lasting, more chip-resistant blades.

“The basic idea is to reduce this heterogeneity, while we keep the high hardness,” Roscioli says. “We’ve learned how to make better blades, and now we want to do it.”
 
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Do you really need MIT to tell you that using a razor or knife will make it dull?


Many of these study are don’t because of Federal Funding of thing we know because if common sense.

Not first or last time Government spent money studying something they already knew answers too.
 
Me too!!!
Oh man, this has taken a turn to the dark side. I say we all stop what we’re doing until things stabilize and we can have MIT give us an answer.
 
I noticed that after a few shaves, my soap puck got smaller. I wonder what's up with that?
MIT has found out that soap puck gets smaller due to 2 main contributing factors. The first is the homogeneousness of the soap, Secondly, is the angle of attack when using the brush on the soap. The researchers have filed a provisional patent on a process to manipulate soap into a more homogenous form, in order to make longer-lasting, more brush abrasive-resistant soaps.
 
“Our simulations explain how heterogeneity in a material can increase the stress on that material, so that a crack can grow, even though the stress is imposed by a soft material like hair,” Tasan says."
Heterogeneity in a material is only a small part of the issue causing edge wear/micro chipping.
The condition of the edge apex and the depth and shape of the striations left by honing is much more important.
This is a microscope image of a sharp v notch chip caused by a fine vetrified diamond plate.
If the hair hits adjacent to this crack the edge will be quite weak.
In fracture mechanics you need a stress concentration in order for a crack to grow. A fine grained steel helps, but if you don't do anything with the cause, ie. the notch/crack the crack will still grow.

IPC_2023-04-28.20.29.44.3960.jpg
 
Heterogeneity in a material is only a small part of the issue causing edge wear/micro chipping.
The condition of the edge apex and the depth and shape of the striations left by honing is much more important.
This is a microscope image of a sharp v notch chip caused by a fine vetrified diamond plate.
If the hair hits adjacent to this crack the edge will be quite weak.
In fracture mechanics you need a stress concentration in order for a crack to grow. A fine grained steel helps, but if you don't do anything with the cause, ie. the notch/crack the crack will still grow.

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Interesting learning all this stuff from that article, and also the more nuanced angles from the educated and experienced pros on this forum. I'm big into theory crafting when it comes to my hobbies and all this is enlightening for sure. Half the fun is chasing perfection, or the term I learned from this forum, the unicorn edge?
 
Interesting learning all this stuff from that article, and also the more nuanced angles from the educated and experienced pros on this forum. I'm big into theory crafting when it comes to my hobbies and all this is enlightening for sure. Half the fun is chasing perfection, or the term I learned from this forum, the unicorn edge?
 
Interesting learning all this stuff from that article, and also the more nuanced angles from the educated and experienced pros on this forum. I'm big into theory crafting when it comes to my hobbies and all this is enlightening for sure. Half the fun is chasing perfection, or the term I learned from this forum, the unicorn edge?

It's interesting that a lot of people at MIT actually seem to acknowledge the existence of unicorns: Who's next to $1 billion? Three MIT Sloan alumni on 'unicorns' list | MIT Sloan - https://mitsloan.mit.edu/ideas-made-to-matter/whos-next-to-1-billion-three-mit-sloan-alumni-unicorns-list.

4749-MIT Unicorn with Tee Shirt_media.jpg
 
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While the videos are interesting to watch, they miss the point that a razor blade is, planned obsolescence.

I am sure that razor blade manufacturing companies could make a blade that would last longer, but why? They are making a fortune with their current marketing plan and a razor blade that is good enough.
 
I do think that it is cool to see this stuff up close. There was another study at MIT a few years back about how cat's drink milk. To the best of my knowledge, there were a number of theories out there, but no one had actually taken and studied high-speed video of the act.

 
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