Calculation of heat regimes for a Ni-Al surface alloy formed on a carbon steel substrate with a low-energy high-current electron beam

Abstract

In the present work, the calculations of heat regimes for a Ni-Al surface alloy formed on a carbon steel substrate using a low-energy high-current electron beam (LEHCEB) were carried out for two types of multilayered systems with different numbers and thicknesses of the layers. The multilayered system of type 1 was three layered system Ni (0.5 µm)-Al (1.52 µm)-Ni (0.5 µm). The multilayered system of type 2 consists of 10 layers of Ni (0.1 µm each) alternating with 9 layers of Al (0.167 µm each). The total thickness of coating deposited in both cases was 2.5 µm. The melting thresholds for Ni, Al and carbon steel during LEHCEB irradiation were determined by the calculation. The phase diagrams obtained in calculation showed that process of melting occurs similarly for both types of multilayered systems. The calculation demonstrated that the melt thickness on the surface after irradiation by LEHCEB with optimal parameters is about 3 µm, and the average lifetime of the melt is ~ 1 µs (Ni-layers), and ~ 10 µs (Al-layers).