Turbochargers may be used in an engine system to increase a pressure of air supplied to the engine for combustion. In one example, the turbocharger includes a turbine coupled in an exhaust passage of the engine which at least partially drives a compressor via a shaft to increase the intake air pressure. Exhaust gas passing through the turbine rotates the blades of a turbine disc, which is coupled to the shaft. The performance of the turbine disc assembly (bladed disc assembly) or turbine blisk (integral bladed disc) may be achieved by controlling the blade tip clearance between the blades/buckets and a turbine shroud. Depending on operating conditions, the turbine disc may rotate at speeds exceeding 25,000 RPMs. In the event of degradation of the turbine resulting in release of part or the entire turbine disc, catastrophic damage to the turbine, as well as other system components in the vicinity of the turbine, may occur if the released turbine disc fragments are not contained.
To contain a released turbine disc, the turbine shroud, typically designed to provide turbine performance, may be designed to absorb the impact of any released disc fragments. However, material and packaging constraints may result in regions of the shroud that are unable to withstand the impact of a high-energy fragment release, particularly when the shroud is subject to the high temperatures present in the exhaust of an engine.