> An elusive material that scientists have wanted to make for decades has finally been synthesised under tremendous heat and pressure...
> The samples are just 5 micrometres across and 3 micrometres deep, and scaling-up production could be difficult...
> ... much more expensive than diamond to buy. But Laniel says the material has benefits that diamond doesn’t, such as generating an electrical signal under pressure, which could make it useful in sensors. Its high energy density could also make it a powerful explosive...
Far more expensive than diamond, not as hard, and it's explosive to boot. I'm not seeing much reason to scale up production.
I was reacquainted with Titanium Nitride care of a woodworker on YouTube the other day. It’s being used to protect tool surfaces from wear. Is that a coincidence or is there something special about nitrogen as a dopant?
> Like carbides, nitrides are often refractory materials owing to their high lattice energy, which reflects the strong bonding of "N3−" to with metal cation(s). Thus, cubic boron nitride, titanium nitride, and silicon nitride are used as cutting materials and hard coatings. Hexagonal boron nitride, which adopts a layered structure, is a useful high-temperature lubricant akin to molybdenum disulfide.
Beyond that, when it comes to cutting tools in particular, there's often interesting solid phase and surface chemistry with layered gradients of oxynitrides forming at depth from the working interface that have similar properties to the base nitride and absorb energy through multiple phase changes and chemical dissociations before ultimate mass reduction, extending the life of the working surface
Less hard, to be more precise [1]. “Strong” and “weak” are way imprecise terms in engineering.
The simplest example is whether it’s strong under pressure (a brick is, a rope isn’t) or under tension (a rope is, a brick isn’t), but there are tons of other properties that are an indicator of strength of a material (https://en.wikipedia.org/wiki/Strength_of_materials), and this may beat diamond in some of them.
[1] reading Wikipedia, even that isn’t simple: “There are three main types of hardness measurements: scratch, indentation, and rebound. Within each of these classes of measurement there are individual measurement scales. For practical reasons conversion tables are used to convert between one scale and another.”
The paper is available if you do a bit of digging. Following the name of the principal investigator goes to his site. The paper is not in his list of publications (one would think an academic would be a stickler about updating that?) but the news link leads to the institution's news story about that research¹. It's worth a read since it's more detailed than the New Scientist article without being as dense as the paper itself. At the bottom of the institution's news story is a link to the paper² which is freely available.
So if anyone is wondering what the "more chemically accurate name would be a mouthful refers to" (oP8-CN, tI14-C₃N₄, hP126-C₃N₄, and tI24-CN₂ were the carbon nitride forms produced) or what the "powerful explosive" mention refers to ("Energy density calculations were performed for the four C–N compounds with respect to decomposition into graphite and molecular nitrogen, at ambient conditions. They revealed that they have a high gravimetric energy density, comparable to or higher than that of TNT for oP8-CN, tI14-C₃N₄, hP126-C₃N₄,and for tI24-CN₂, a value even higher than for RDX..."), it's all there.
- "[Cyanuric triazide] was an energetic compound with possible sensitivities toward heat, friction, impact, and discharge. Although no incidents occurred during the experiments, personal safety equipment such as protecting helmets, face shields, ear plugs, leather coats, Kevlar gloves, and grounded shoes as well as grounded equipment were strongly recommended."
This looks fun to work with [0]. It has a molecular formula of C3N12. Derek Lowe wrote a "Things I Won't Work With" column about cyanogen azide [1], which is CN4; this seems to be some kind of trimer form of that one. (Which one is worse?)
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[ 1.1 ms ] story [ 42.8 ms ] thread> The samples are just 5 micrometres across and 3 micrometres deep, and scaling-up production could be difficult...
> ... much more expensive than diamond to buy. But Laniel says the material has benefits that diamond doesn’t, such as generating an electrical signal under pressure, which could make it useful in sensors. Its high energy density could also make it a powerful explosive...
Far more expensive than diamond, not as hard, and it's explosive to boot. I'm not seeing much reason to scale up production.
2. Useful as a pressure sensor in high force assemblies.
> Like carbides, nitrides are often refractory materials owing to their high lattice energy, which reflects the strong bonding of "N3−" to with metal cation(s). Thus, cubic boron nitride, titanium nitride, and silicon nitride are used as cutting materials and hard coatings. Hexagonal boron nitride, which adopts a layered structure, is a useful high-temperature lubricant akin to molybdenum disulfide.
Beyond that, when it comes to cutting tools in particular, there's often interesting solid phase and surface chemistry with layered gradients of oxynitrides forming at depth from the working interface that have similar properties to the base nitride and absorb energy through multiple phase changes and chemical dissociations before ultimate mass reduction, extending the life of the working surface
Less hard, to be more precise [1]. “Strong” and “weak” are way imprecise terms in engineering.
The simplest example is whether it’s strong under pressure (a brick is, a rope isn’t) or under tension (a rope is, a brick isn’t), but there are tons of other properties that are an indicator of strength of a material (https://en.wikipedia.org/wiki/Strength_of_materials), and this may beat diamond in some of them.
Reading https://en.wikipedia.org/wiki/Material_properties_of_diamond, diamond isn’t particularly tough, and we don’t really know its tensile strength, so this is less hard, but may have higher toughness or higher tensile strength.
[1] reading Wikipedia, even that isn’t simple: “There are three main types of hardness measurements: scratch, indentation, and rebound. Within each of these classes of measurement there are individual measurement scales. For practical reasons conversion tables are used to convert between one scale and another.”
[1] https://en.wikipedia.org/wiki/Borazon
So if anyone is wondering what the "more chemically accurate name would be a mouthful refers to" (oP8-CN, tI14-C₃N₄, hP126-C₃N₄, and tI24-CN₂ were the carbon nitride forms produced) or what the "powerful explosive" mention refers to ("Energy density calculations were performed for the four C–N compounds with respect to decomposition into graphite and molecular nitrogen, at ambient conditions. They revealed that they have a high gravimetric energy density, comparable to or higher than that of TNT for oP8-CN, tI14-C₃N₄, hP126-C₃N₄,and for tI24-CN₂, a value even higher than for RDX..."), it's all there.
¹ https://www.ph.ed.ac.uk/news/2023/breakthrough-in-synthesis-...
² https://onlinelibrary.wiley.com/doi/epdf/10.1002/adma.202308...
Nice! Would make for a exciting day on the milling machine
- "[Cyanuric triazide] was an energetic compound with possible sensitivities toward heat, friction, impact, and discharge. Although no incidents occurred during the experiments, personal safety equipment such as protecting helmets, face shields, ear plugs, leather coats, Kevlar gloves, and grounded shoes as well as grounded equipment were strongly recommended."
This looks fun to work with [0]. It has a molecular formula of C3N12. Derek Lowe wrote a "Things I Won't Work With" column about cyanogen azide [1], which is CN4; this seems to be some kind of trimer form of that one. (Which one is worse?)
edit: Also this column [2] is about C2N14.
[0] https://en.wikipedia.org/wiki/Cyanuric_triazide ("Cyanuric triazide")
[1] https://www.science.org/content/blog-post/things-i-won-t-wor... ("Things I Won't Work With: Cyanogen Azide")
[2] https://www.science.org/content/blog-post/things-i-won-t-wor... ("Things I Won't Work With: Azidoazide Azides, More Or Less")
How about all three in one device?
I will take one of those, and a case of whisky.