I checked this, and this post is correct. At least, when you’re talking about bones and common, natural diamonds, which are monocrystalline.
The toughness of bone is about 2-4MPa√m(depending on the exact form of toughness) and can increase to 3-20MPa√m locally as when bones crack, microfractures can deflect the crack from growing along the directions of maximum tensile stress.
As compared to common natural forms of diamond, which only have a toughness of 2MPa√m. Which is mediocre compared to other engineering materials. However! Other naturally occuring forms of diamond, such as Carbando, are much tougher and just as hard. Carbando’s strength comes from the random orientation of microdiamonds i.e. it is not mono-crystaline. There’s little numerical data in the literature on this, but it is predicted that its toughness will exceed 10-20MPa√m (paywalled article with a confusing preview). Some evidence for their toughness comes from industrial usage for thing like deep-drilling bits, unlike regular diamond. Moreover, designed dimaonds have achieved Pareto improvements in toughness and hardness compared to common natural diamonds (reaching upto 26.6MPa√mfor nanotwinned diamond).
So diamonds can be clearly superior to bone. And yeah, these things probably aren’t bound together on a large scale by van der waals forces (I haven’t looked into that aspect for unusual diamonds like Carbando, not an expert, just took a couple solid state physics courses in uni). But. Carbando seems to gain its strength from irregularities. Sometimes irregularities make materials much stronger, sometimes much weaker. Sometimes “fault lines” can be beneficial, because they allow the material to be ductile, which you want. Like the ductility of steel, IIRC, comes from irregularities in the lattice structure which are moved around as the material deforms.
Sometimes irregularities make materials much stronger, sometimes much weaker. Sometimes “fault lines” can be benificial, because they allow the material to be ductile, which you want. Like the ductility of steel, IIRC, comes from irregularities in the lattice structure which are moved around as the material deforms.
And in that deformation (of a metal or other crystal), you both create the discontinuities (esp. dislocations) that increase strength while also introducing brittleness (work hardening). But the highest strength you can get with this kind of process is still not as high as you’d get from a defect free crystal, such as a monocrystalline whisker.
I checked this, and this post is correct. At least, when you’re talking about bones and common, natural diamonds, which are monocrystalline.
The toughness of bone is about 2-4 MPa√m(depending on the exact form of toughness) and can increase to 3-20 MPa√m locally as when bones crack, microfractures can deflect the crack from growing along the directions of maximum tensile stress.
As compared to common natural forms of diamond, which only have a toughness of 2 MPa√m. Which is mediocre compared to other engineering materials. However! Other naturally occuring forms of diamond, such as Carbando, are much tougher and just as hard. Carbando’s strength comes from the random orientation of microdiamonds i.e. it is not mono-crystaline. There’s little numerical data in the literature on this, but it is predicted that its toughness will exceed 10-20 MPa√m (paywalled article with a confusing preview). Some evidence for their toughness comes from industrial usage for thing like deep-drilling bits, unlike regular diamond. Moreover, designed dimaonds have achieved Pareto improvements in toughness and hardness compared to common natural diamonds (reaching upto 26.6MPa√mfor nanotwinned diamond).
So diamonds can be clearly superior to bone. And yeah, these things probably aren’t bound together on a large scale by van der waals forces (I haven’t looked into that aspect for unusual diamonds like Carbando, not an expert, just took a couple solid state physics courses in uni). But. Carbando seems to gain its strength from irregularities. Sometimes irregularities make materials much stronger, sometimes much weaker. Sometimes “fault lines” can be beneficial, because they allow the material to be ductile, which you want. Like the ductility of steel, IIRC, comes from irregularities in the lattice structure which are moved around as the material deforms.
And in that deformation (of a metal or other crystal), you both create the discontinuities (esp. dislocations) that increase strength while also introducing brittleness (work hardening). But the highest strength you can get with this kind of process is still not as high as you’d get from a defect free crystal, such as a monocrystalline whisker.