Liquids fracture like solids—what breaking point?

Liquids can fail like solids—when and why

Researchers at Drexel University reported that under the right conditions, liquids can fracture in a way that resembles how solids break. The key idea is that a liquid isn’t always a “soft” medium that only flows. When stresses are applied in the right manner—at the right scales and with the right constraints—its internal structure can support crack-like failure patterns.

This matters because fluid mechanics and fracture mechanics have traditionally been treated as separate toolkits: fluids are characterized by flow and instabilities, while fracture models focus on crack propagation in solids. The Drexel work suggests that, in at least some regimes, the boundary between the two descriptions blurs. That could improve predictions in engineering settings where liquids experience rapid deformation or extreme stresses, such as microfluidic devices, materials processing, and other systems that involve fast, violent pressure changes.

The practical takeaway is not that every liquid shatters like glass. Rather, there is a specific regime—described in terms of the conditions that enable crack initiation and growth—where a liquid can exhibit a definite “breaking point.”

If those conditions can be mapped and reproduced reliably, designers could better anticipate failure modes in systems that rely on liquids, and physicists could test more unified theories of how matter transitions from flowing behavior to brittle-like rupture.

• The study argues that fracture-like behavior appears only under particular experimental circumstances.
• It challenges the long-standing separation between fluid mechanics and fracture mechanics.
• Potential impacts include safer designs for devices and industrial processes involving stressed liquids.