The purpose of this study was the research for a non-standardized method of measuring the shear bond strength at constant compression force and compare with the shear testing methods on cylindrical and prismatic samples, like DIN 50161:1977-10, DIN EN15340-2007. The conducted comparative analysis showed a significant shortcoming of the well-known methods for assessing the shear bond strength on samples for industrial application. The main one is an inability to measure the “actual/real” adhesion shear strength of thermal spray coatings for industrial parts. The shear bond strength of plasma-sprayed coating MgAl2O4 with thickness 0.30-has been investigated by applying the prismatic samples (linear dimensions of shear area 1.5-), using Nanovea scratch tester at compression forces ranging from 1 to 70 N. Shear force-displacement curves get essential information about adhesion/cohesion, delamination and cracking properties of thermal spray coating. An increase of shear forces is primarily associated with a rise in friction forces at the coating delamination boundary. Applying for parts of the ITER blanket modules, this research has demonstrated the importance of practical application of the shear testing results at compressive loads for ensuring product life.

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The effect of the sliding speed on friction and wear characteristics of plasma sprayed ceramic coatings (Al 2 O 3 -13% TiO 2 , ZrO 2 -8% Y 2 O 3 , Al 2 O 3 modified) was studied. Plasma sprayed coatings are not hard and have high layered structure. Abrasion of coatings in the friction pair with steel and bronze counter bodies occurs through brittle detachment conglomerated regions with low cohesive resistance. The modified coating (Al 2 O 3 ) has the highest wear resistance and the lower coefficient of friction compared to the coatings (Al 2 O 3 -13% TiO 2 , ZrO 2 -8% Y 2 O 3 ) in the studied velocity range (0.1-10 mm/s). Laser melting can be used as an efficient way of increasing the tribotechnical properties of plasma sprayed oxide coatings.