STUDY OF THE EFFECT OF TITANIUM INTRODUCTION INTO THE FLUX-CORED WIRE COATING OF THE Fe‒C‒Si‒Mn‒Сr‒Mo‒Ni SYSTEM

Abstract

To increase the wear resistance of products to abrasive wear, various electric arc coatings are used, applied by cladding method. For this purpose, the flux-cored wires of the Fe‒C‒Si‒Mn‒Cr‒Mo‒Ni system are used. The effect of introducing titanium microadditives into flux-cored wires has been studied. To apply them to plates made of steel 09G2S, a welding tractor ASAW-1250 was used. The properties of the fused layers containing carbon (0.19‒0.24%), titanium (0.014‒0.025%), chromium (3.23‒6.54%), manganese (1.16‒1.55%), silicon (0.63‒0.98%), molybdenum (0.62‒0.72%), aluminum (0.013‒0.023%) with an increased sulfur content (0.058‒0.076%) were investigated. The chemical composition of the deposited metal was determined by the X-ray fluorescence method using the XRF-1800 spectrometer and the atomic emission method on the DFS-71 spectrometer. The microstructure of the electric arc coatings was studied using the OLYMPUS GX51 optical microscope. The study of phase and elemental composition was carried out by scanning electron microscopy methods using the MIRA 3 LMH device. It has been established that the microstructure of welded coatings is lower bainite of varying degrees of dispersion, which is due to the significant content of chromium and the low carbon content in the deposited metal. In the composition of the non-metallic phase of the deposited metal there are fluorine compounds, oxide and sulfide inclusions. According to the data obtained, the dependencies of the influence of the chemical composition of the cladding on the hardness and rate of wear are con-structed. All the studied experimental coatings have a characteristic structure and consist of zones: deposited metal, thermal influence, recrystrallized grain. In the metal of all samples of experimental coatings there are large inclusions containing fluorine atoms trapped from flux, in combination with oxygen and iron atoms. The size of such inclusions reaches 30 μm. A large number of globular inclusions of manganese sulfides were detected, due to the significant sulfur content in the composition of the cladding materials, as well as silicon and aluminum oxides. Based on the results of the research, the measures have been developed that allow cladding with the studied flux-cored wire under welding fluxes with a high sulfur content without deterioration in the quality of the deposited layer.