THERMAL SPRAY METHOD FOR PRODUCING VERTICALLY SEGMENTED THERMAL BARRIER COATINGS

摘要

The invention provides a method for forming a thermal barrier coating having vertical cracks for improved thermal and mechanical stress tolerance. The method can include depositing a first sub-layer on a substrate at a first temperature T1, followed by depositing a second sub-layer on the first sub-layer at a second temperature T2, wherein T2 is less than T1 such that a temperature gradient having a negative heat flux toward the top of the second sub-layer is created, thereby introducing thermal stress in the sub-layers causing vertical cracks to be formed in the sub-layers. The method then involves repeating steps (a) and (b) for n cycles to form the thermal barrier coating comprising the vertical cracks, wherein n is an integer from 1 to 200.