Papers by Author: Evgeniy Golovin

Abstract: The cladding of titanium and graphite powders on the cp-titanium workpieces using the electron beam injected to the atmosphere provided the formation of the surface layers with a high content of high-strength carbide particles. The main structural components in cladded layers are α-Ti (αʹ-Ti), titanium carbide and graphite. Electron beam current is the main technological parameter defining a thickness of the hardened layer. An increasing beam current ranged from 20 to 23 mA leads to the cladded layer growth up to 2.9 mm. However, in this case a significant decrease of the microhardness level and the wear resistance level of the cladded layer is not observed. An average microhardess value of the hardened layer is of 430 HV. Under the conditions of friction against fixed abrasive particles, a wear resistance level of the cladded layers is by 32-45 % larger than that of cp-titanium.

Abstract: Multilayer materials produced by explosive welding of low carbon steel were investigated. Non-uniform structure of interlayer boundary was characterized using visible light microscopy, SEM and TEM. It was shown that 4 zones with different structure and mechanical properties present in the welded seams. To estimate fatigue properties of the multilayer materials kinetic diagram of fatigue failure were used. It was revealed that larger boundary waves give more significant contribution to fatigue crack resistance. In experiments carried out in the current research number of cycles to failure of multilayer materials was higher than those for bulk materials.

Abstract: Structure, microhardness and fracture features of coatings produced by atmospheric electron-beam cladding of amorphous boron were investigated. The coatings were produced by cladding of one, two and three layers of powder. Produced coatings thickness is 550, 750 and 900 μm respectively. The peak level of microhardness is 14000…16000 MPa. By the means of XRD analysis it is stated that the main phases of strengthened layers are FeB and Fe₂B borides and eutectic (α-Fe + Fe₂B). The coatings after one layer cladding have non-uniform structure with microvolumes having lack of borides. Three-layered coatings are noted for their high brittleness. The best properties are presented by two-layer coatings.