Effect of substrate conductivity on the evaporation of small sessile droplets.

Here we show the effect of the thermal conductivity of the substrate on the evaporation process of small droplets. We deposited small droplets on the order of 100-500 μm in diameter on four different substrates with different thermal conductivities and surface properties, and we measured the evaporation time. Also, a numerical model that describes this process was developed to include thermal effects inside the droplet and heat transfer from the substrate. Our model considers the entire time of evaporation including the pinned and depinned stages. This model uses a new approach for the contact line behavior. It uses experimental results to define the movement of the contact line as a function of the contact angle.