Development of a shear-tensile testing method to qualify metal spraying technologies

The metal spraying is widely used process to extend the resistance against to wearing, erosion or corrosion. The related standard defines these surface protective methods as special processes because these cannot be qualify by a non-destructive testing method which clearly states the fulfilment of the requirements of a given work. Therefore the quality of the given surface protective method can be determined only during the later use. The main goal of this work is to define a control method which can be used for qualify the given metal spraying method. In our work the used base material as carrier material was P235GH steel and we investigated 6 different metal sprayed layers. To avoid the stress concentrator areas (small cracks) on the surface before the test the surface was grinded and EDM was used to cut out the samples from the manufactured work pieces. To investigate the properties of the sprayed layers tensile tests were used. From the data the strength of the composites and the layers can be calculated. Based on the shear-tensile test we created a calculation method which can be used to qualify the metal spraying methods before its use. (paper)