The operating temperature at which jet engine blades are able to safely rub against abradable shroud linings has been dramatically increased from 350 to 1200°C. This has been made possible by executing wear mechanism studies and by close collaboration with major engine manufacturers.
Methods of Increasing Gas Turbine Engine Efficiency

In the last two decades, air traffic volume has increased considerably, whereas the total quantity of fuel consumed has remained almost unchanged. The jet engine manufacturers strongly contributed towards this by increasing engine efficiency and power generation. This was achieved by raising the operating temperatures, by the use of efficient aerodynamic design and by the use of lightweight materials. Because all of these are mature technologies, one of the last means to further increase the efficiency is the reduction of the clearance distance between the blade tip and casing. This increase in efficiency can save airlines significant operating costs. The implementation of abradable coatings also increases the surge margin, thus increasing the stability and active safety of engine flow conditions.
Uses of Abradables

Abradables are not restricted to aeroengines. They can be used in most rotating machinery such as stationary gas turbines, turbo compressors, radial compressors, turbo chargers, and pumps. Sulzer Innotec and Sulzer Metco, in close co-operation with most major jet engine manufacturers, are world leaders in the development of abradable coatings to cope with the operating conditions throughout the jet engine