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The main difficulties of application of high-frequency (HF) heating for sealing by soldering of microblock packages made of aluminum alloys is the low efficiency of heating, long processing time and considerable heating of the internal electronic module while sealing. The purpose of this study was to use effectively the physical phenomena of HF heating in order to optimize the HF heating parameters of sealing by soldering using fusible solders of microwave microblock packages made of diamagnetic alloys. Effects of HF heating (superficial, proximity and concentration of power lines) of the electromagnetic field are applied to sealing using soldering of microwave microblock packages made of diamagnetic alloys. The optimized parameters of HF heating provide energy efficiency and productivity of sealing: frequency of the electromagnetic field and the inductor design. When soldering microelectronic devices containing electronic parts sensitive to the electric field component, the energy of electromagnetic field in the package should be significantly lower than the energy of elements degradation, in which case the skin layer reaches the field penetration depth which is equal to 4 package thickness values. In order to increase the HF heating efficiency, there should be a concentration of the inductor current on the package surface facing the inductor, which is done by using a ferrite magnetic core. Using a ferrite magnetic core inside the inductor concentrates tension of magnetic field due to concentration of power lines of magnetic field in 1,2-1,3 times. The optimal frequency range for HF soldering is 0,4—2,0 MHz when at electromagnetic field penetration depth into the material of the package equal to 4 thickness values of the skin layer, the field strength is 152 times weaker in comparison with the surface.

Current trends in the production of railroad wheels show the use of some promising techniques: a reduction in the carbon content of the finished steel; degassing the steel in a vacuum to decrease its hydrogen content; more efficient deoxidation and alloying of the steel. When used together, these measures are ensuring that the finished steel has the mechanical and service properties prescribed for wheel steel. Studies and factory testing of a new technology for making wheel steel have shown that the oxygen content of the steel can be reduced by its self-deoxidation during vacuum degassing. This approach also helps lower the steel’s hydrogen content while saving deoxidizers. Researchers have discovered certain laws that govern the relationship between the characteristics of wheel steel and its contents of sulfur and gases. The amount of sulfur and gases in this type of steel can be reduced by using efficient parameters for the treatment that is administered outside the steelmaking furnace.

The deformability of several powder ferroalloys (of rare-earth metals, Zr, Ti), titanium sponge, and graphite in a metallic matrix during the rolling of laboratory and commercial ingots was experimentally investigated. It is shown that it is technically possible to hot roll and cold draw composite ingots with powder inserts of the given materials

The thermophysical properties of certain ferroalloy (FS30R3M30, FSZr50, FTi-30) and graphite powders, used for the composite microalloying of steel castings, were determined using an experimental—calculation method. A substantial difference in the heat conductivity of powder and monolithic materials was revealed. The nature of change of these properties with temperature was investigated.