goniometer

Last week I learned to use a new machine – a goniometer. One of the things a goniometer does is measure the contact angle of droplets on surfaces. You can dispense some liquid out of the dropper onto a flat surface, the vision system captures data, and the software analyzes what angle is formed between the droplet and the surface. Why is this useful? For my research, I needed to learn more about the surface properties of some materials I was interested in. If you know the contact angles of various known liquids on an unknown material, you can calculate things like the surface energy of the material. Then you can make some progress toward figuring out the work of adhesion on that surface, or the fracture energy between two surfaces. So I thought this would be easy. Put drop on surface, measure contact angle. But the key here is […]