The catastrophic failure in a plasma recycling plant began with the detachment of the inner ceramic coating. The protective layer, applied via thermal spraying (plasma spray), separated from the metallic substrate, causing the reactor's outer shell to melt due to direct exposure to the plasma arc. Subsequent analysis required a 3D reconstruction of the ablation phenomenon to determine the root cause between cyclic fatigue and application error.
Differential diagnosis using SimScale and GOM Inspect 🔥
The engineering team used GOM Inspect to scan the residual geometry of the reactor, creating a point cloud of the ablated area. This real model was imported into SimScale to run a finite element method (FEM) simulation of thermal stress. Two scenarios were compared: a coating with perfect adhesion subjected to thermal cycles of 1200°C, and another with a defective interface simulating a poor plasma spray application. The results showed that the failure zone coincided with the stress concentration in the poor adhesion model, ruling out pure fatigue as the primary cause.
Lessons on thermal coating inspection ⚠️
The correlation between the simulated and actual ablation showed that the detachment was not due to gradual cracking, but to sudden delamination at the ceramic-metal interface. This reinforces the need to validate plasma spray processes with 3D non-destructive testing before startup. In extreme thermal fatigue environments, digital inspection with GOM and prior simulation in SimScale are not optional; they are the only way to prevent shell melting.
How can the propagation of submillimeter cracks in the ceramic lining of a thermal plasma reactor be modeled in 3D to predict the exact point of catastrophic detachment under thermal stress cycles?
(PS: Material fatigue is like yours after 10 hours of simulation.)