Changes in processing parameters strongly affect the structure and properti
es of thermally sprayed coatings and, consequently, their performance. Resi
dual stress in the deposits is a factor that needs consideration, since it
has direct influence on the processability and integrity of the sprayed mat
erial. In order to enhance the understanding of this phenomenon, a study of
measurements of residual stresses on a single particle level was undertake
n. The deposit is built-up with the successive impingement of micron-sized
droplet and therefore an understanding of the single splat microstructure a
nd properties will provide a fundamental understanding of the underlying me
chanisms. Residual stresses in thin coatings, as well as isolated particles
-splats-deposited on stainless steel substrates were investigated using X-r
ay microdiffraction. Plasma sprayed molybdenum and cold sprayed copper were
studied. The key process parameters considered were: in-flight particle en
ergy and substrate temperature in the first case, and particle velocity in
the latter. The results will be discussed with respect to the influence of
each of these parameters, contribution of quenching and thermal stress comp
onent and splat formation. Further, the coating build-up from individual pa
rticles and the associated factors influencing residual stress will be disc
ussed. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All
rights reserved.