For generations, scientists have treated liquids and solids as fundamentally different: solids crack under stress, while liquids simply flow. However, new research involving scientists from Drexel University is reshaping this long-held belief by showing that liquids can also fracture under the right conditions.
When Flow Turns Into Fracture
In collaboration with international researchers, Drexel scientists studied polymer-based liquids, which typically behave like fluids. To test their limits, the team stretched these liquids rapidly while recording the process with high-speed cameras. Instead of thinning smoothly, the liquid suddenly formed cracks that spread through it, much like fractures in solid materials.
This observation challenges the traditional assumption that only solids can crack and shows that liquids can exhibit solid-like failure when exposed to extreme stress.
A Measurable Breaking Point
The researchers also identified a clear breaking threshold. When the applied stress exceeds a critical level, the liquid stops flowing and fractures abruptly. Unlike solids, these liquids often generate multiple cracks simultaneously, rather than breaking from a single weak spot.
This behavior suggests that the fracture process depends more on how quickly and forcefully the material is deformed than on pre-existing defects.
Blurring the Line Between States of Matter
Drexel researchers continue to explore how materials bend, break, and deform under stress, revealing that behavior can shift dramatically depending on internal structure and external forces.
Together, these findings show that the boundary between solids and liquids is far more flexible than once believed. Under certain conditions, liquids can behave like brittle solids, opening new possibilities for material science and industrial applications
