The latest Formlabs resin is called Tough 1500 and is positioned in toughness right between Tough V5 and Durable.
Here's a quick comparison between the three resin:
Tough 1500 is compatible with the Form 2, Form 3/3B, and Form 3L.
On a surface level, that's all you need to know but we'll expand a bit more about material properties. It's time to put your smarty pants on because this is going zero to 1500 really quick!
Your next questions might be:
Let's tackle the easy one first,
What is the 1500 all about?
That's the resin's tensile modulus in Megapascals (a unit of pressure or load over an area) and that's an important material property that measures elasticity.
What's Elasticity?
In order to understand what toughness is let's first define elasticity. Elasticity is the material's ability to strain/deform in a non-permanent way. Think about how a spring pops right back up to its original shape once you release the load or how your phone case can be crumpled and return right back into its original shape.
In general, when the tensile modulus increases, so does the materials' resistance to elastic deformation. In other words, a material is harder to bend/deform and has a shorter deformation window before switching from elastic to plastic deformation.
What's Toughness?
Once a part enters plastic deformation it will no longer return to its original shape when the load is removed. That doesn't necessarily mean our part failed. At this point, our part can still absorb energy or take on more load without fracturing.
The amount of energy your part can absorb during plastic deformation and before the part ultimately fails decides the toughness of the material.
So what's so special here?
Let's rename the current Tough V5 and Durable to something we can compare better:
So now we have three resins from least to most elastic that can fit different applications instead of two resins on the extreme spectrums. This opens up more applications and an opportunity to match our prototyping material closer to our end-product material.
Note that the toughness of a material isn't easily determined from the above numbers and a deeper understanding of material properties is necessary. Some terms and concepts to research would be:
