Structure and characteristics of a thin-layer "aluminum - carbon nanotubes" sandwich structure

The study describes a way to produce thin-layer sandwich structures containing layers of aluminum foil and an interlayer filler of carbon nanotubes (CNTs). To obtain a homogeneous structure of the composite, induction heat treatment was used combined with a device providing primary compression of the assembly. To determine the functional characteristics of sandwich structures, the homogeneity of their microstructure and surface conductivity were studied. It was found that the use of CNTs allowed increasing the surface conductivity by a factor of 8.3–9.5 compared to the sandwich structure without filler.

Study of the hardness distribution after induction heat treatment of titanium over the surface and the cross-section

In this work, the mechanical properties (microhardness) of a titanium disk after induction heat treatment (IHT) were studied. The influence of the processing parameters (inductor current and temperature) on the distribution of microhardness over the cross-section of the experimental samples was established.

Research of the structure and mechanical properties of gas-thermal coatings after induction heat treatment

In this article the process of induction-thermal modification of titanium coatings formed by electroplasma spraying was considered. The influence of the inductor current on the temperature of processed samples was experimentally established. The research results showed that thermal treatment of the samples with titanium coatings at a temperature of 750–1200 °C and a duration of 300 s led to an increase in porosity from 56±2 to 61±1 % and in microhardness from 1035–1532 to 1825–1883 HV0,98, the sprayed layer thickness decreased from 320±30 to 114±15 μm as well. A change of nanoscale structural elements shape was also observed.

Induction-thermal action effect on the surface area of titanium products

The changes in the surface area of titanium samples occurring during induction heat treatment (IHT) were studied. The dependence of the surface area of titanium samples on the exposure temperature was revealed. When a titanium sample was heated to a temperature of 1000 °C in the air at an exposure time of 60 s, there was a 45-fold area increase. The assessment of the porosity of the formed coating is carried out. The number of pores increased with increasing temperature from 374 to 1029 pieces. Accordingly, the average pore size decreased by 40%.

Optimized Nitriding for Subsequent Induction Heat Treatment

Nitriding is used to achieve a high hardness in the surface layer through the precipitation of nitrides. However, to realize high nitriding hardness depths, treatment times of many hours are necessary, which usually also result in a decrease in strength within the nitrided layer and base material. With induction heat treatment, on the other hand, high hardness depths can be achieved in a very short time. However, the maximum hardness increase is limited by the alloy content of the material. By combining nitriding and induction hardening, high hardness depths can be achieved in short treatment times as an alternative to deep nitriding. In addition to a significant saving in process energy surface layer properties that cannot be achieved with the individual processes are expected. In order to fully exploit the potential of the combination treatment, at first suitable conditions must be set during nitriding for the subsequent induction hardening. In the present work, nitriding layers with low-porosity compound layers as well as only diffusion layers were produced and analyzed on typical nitriding and tempering steels for this purpose.