As a metalurgist (a long time ago in a distant galaxy called working for a living) you may be interested to know that all turbine blades are single crystals, from the root to the tip. This is because at high temperatures the grain boundary, the interface between the crystals, is an area of high energy suseptable to chemical attack and is the first part of a metal to melt allowing creep at high temp.
Also the nimonic alloys used for turbine blades are prone to corrosion in salty atmospheres, which is why turbine blanks are always fitted to carrier aircraft, and turbine washing routinely carried out.
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