Investigation of residual stress generation in plasma-sprayed hydroxyapatite coatings with various spraying programs

► Hollow holder with back cooling leads to the tensile residual stress in the HAC. ► HAC with the front cooling displays the compressive residual stress. ► Residual stress is depended on the spray program not always tensile or compressive. ► Spraying program results in the various temperature gradients. ► The optimal temperature gradient will be achieved.