Optimization of the Machining Process of NiCrBSi Thermal Spraying

Nowadays, the requirements for the properties of machine parts are increasing. With this trend, the application of thermal spraying is also growing. The main reason for the use of thermal spraying in industry is to increase the resistance to mechanical wear, corrosion and oxidation. At present, thermal sprays are machined using grinding technology due to their high hardness. The roughness Ra of the thermal spray after the application is around 7 µm. Such a large surface roughness is not very suitable for the functional purposes of the sprayed surface. Machining of the coating is therefore necessary to obtain less surface roughness and to achieve geometric and dimensional tolerances. The article describes the sequence and evaluation of the experiment in turning NiCrBSi thermal spraying under different cutting conditions. The effect of cutting speed and feed on the roughness value of the machined spray surface was investigated. Three types of cutting materials in the form of sintered carbide, cubic boron nitride and polycrystalline diamond were used for machining. The output was to find optimal cutting conditions depending on the surface roughness and the amount of insert wear