Study of the structure and properties of products made of heat-resistant alloys based on Ni-Cr-CrN with a high nitrogen content by direct metal laser sintering
Abstract:
This work presents a study of the preparation of additive materials based on a nickel-chromium alloy of the Ni-Cr-CrN system by direct metal laser sintering (DMLS). The additive materials were produced on the EOS M270 setup (with the option of open editing modes). The research range: laser radiation from 100 to 200 W, the speed of the laser beam from 600 to 1100 mm/s. The chemical composition of the obtained materials is investigated. The composition indicates a high final content of nitrogen in the alloy (0.5%). The structure of the obtained samples and their mechanical characteristics, namely, the bending strength (1500 MPa) and Vickers microhardness (450 HV), have been investigated. The morphology, microstructure, and elemental analysis of the initial powder and the resulting additive materials were studied by scanning electron microscopy and X-ray spectral microanalysis on the TESCAN Vega research complex. Analysis of the structure shows that the elements Ni, Cr and Fe are distributed evenly over the entire area of the samples, which indicates a uniform Ni-Cr-CrN melt.
Keywords:additive technologies, direct metal laser sintering, self-propagating high-temperature synthesis, nitrided nickel-chromium alloy, microhardness, bending strength.