Study of the Composition and Properties of Coatings being Formed during Combustion of Al + B2O3 Mixtures on Steel Substrates

Within the scope of this work, the methods of the experimental research of SHS processes during HFC-heating, particularly of hardening coatings applied on samples by HFC-heating have been developed. A study of the composition and properties of the products formed during the SHS process in the basic mixture on the surface of S355 steel parts during HFC-heating has been made, and it has been shown that aluminum oxide, aluminum nitride (by-product), and amorphous boron are formed under these conditions, and composite porous inhomogeneous coatings up to 250 microns thick, based on aluminum oxide, SHS products in the basic mixture and traces of high-speed HFC-boriding products are formed on the workpiece surface.

Preparation and Optical Application of SiO2-TiO2 Composite Hardening Coatings with Controllable Refractive Index by Synchronous Polymerization

The homogeneous SiO2-TiO2 composite sols were prepared by organic-inorganic synchronous polymerization with titanium isopropoxide and tetrabutyl silicate as precursor. The organic-inorganic composite hard coating with Si-O-Ti as the framework was prepared by adding compound crosslinkers (up-401) and 3-Methacryloxypropyltrimethoxysilane (KH-560). The structure of the coating and the hardened film were characterized by infrared spectrum, scanning electron microscopy, atomic force microscopy, particle size analyzer and thermogravimetry. The refractive index, transmittance and hardness of the hardened film were measured by ellipsometry, UV-Vis spectrophotometer and hardness tester. By adjusting the ratio of Si/Ti and optimizing the reaction conditions, the hardness of the hardened film could reach 6H, and the refractive index could be adjusted from 1.55 to 1.76. At the same time, the application of hard coatings on the surface of optical lens were studied.

On effect of tool materials coating on surface roughness treated during turning of stainle

The requirements for the surface quality of parts are steadily growing, including for parts made from stainless steels, the scope of which is rapidly expanding. Surface roughness is largely the result of a large number of processes occurring in the cutting technological system. For most cases, the roughness is regulated by the parameters Ra and Rz. This paper describes the dependence of the surface roughness of parts on the hardening coatings applied to the carbide replaceable plates of turning cutters, presents the results of the corresponding studies of the surface roughness by a large number of parameters as applied to the turning of specialized stainless steels.

Combined method of hardening and finishing abrasive treatment of parts surfaces in magnetic field

Method and technologies of coating metal surfaces by electric spark discharges with subsequent hardening abrasive treatment in a magnetic field are considered. The possibilities of increasing the wear resistance of metal surfaces by joint method of alloying the surface layer of the part and reducing its roughness are shown. Mathematical models of these processes have been developed, which make it possible to optimize the technologies of hardening coatings.

Optimal electroacoustic coating modes investigation for production of nanostructured materials

Described the research results of hardening coatings coating modes influence on the microstructure of the surface layer of machine parts. Electroacoustic coating was used as a coating method. X-ray structural analysis and electron microscopy were used to investigate the microstructure of the coatings. The results obtained can be used to determine the optimal technological modes of coating.

Hardening coatings of tool materials for turning of stainless steels

The results of new tool materials designing for processing of stainless steels are presented, which allowed to increase the tool life up to 3 times. The studies are carried out with the integrated use of experimental data and computer simulation in the Deform software environment. The criteria by which modeling is feasible at sufficient level are identified: tool wear, temperature in the cutting zone, stresses in the tool material and tool material deformation.

Rhenium as a Perspective Anodic Material in Materialogy of Surface at Electric Spark of Alloying

Electric spark of alloying – ESA – from the standpoint of materialogy, a new stage in the development of the materials science, is a method of surface hardening that refers to technologies meeting the new development vector of the materials science, including its most important sections – surface materialogy. As an anode material, an unconventional material for the electric-spark coating method (ESA) - rhenium is of practical interest for creating protective and hardening coatings. The results of studies of the formation modes by the method of ESA are given on the surface of steel grade 35 of the alloyed layer and its properties using the anodic material from rhenium is shown. The kinetics of the doped layer formation depending on the ESD regimes, their justification is shown. It is established that with an increase of the frequency of discharge pulses in the range of 1600>fcps>20 Hz, a trend to increase the thickness of the AL hav.AL is observed, and with an increase in energy 1.8>E>0.11 J, on the contrary, there is a trend of its decrease; the latter is associated with a decrease of the pulses frequency with the increase of energy. The obtained series of the efficiency of the ESA process make it possible to predict the achievement of the required parameters of the doped layer using Re as the anode material.