Electric-spark alloying of steels with chromium carbide base alloys

Conclusions It is shown that, of the Cr₃C₂-Fe cermets investigated, KKhZh-50 alloy is the best alloying electrode material. Alloying should be performed under soft conditions (E_pulse ^–2 J). The quality of the reinforced layer depends on the pulse energy and the base and electrode materials. The continuity of the layer increases and its surface roughness and thickness decrease with increasing pulse energy. Anode erosion and alloyed layer formation are affected by the secondary structure on the electron surface. For KKhZh-50 alloy its formation decreases anode erosion and the cathode weight gain, while for KKhNF-15 alloy, by contrast, it increases them. It is proposed that, to increase the corrosion resistance of such coatings (by about two orders), 65G steel should be alloyed in two stages, first with KKhZh-50 cermet and then with nickel.Translated from Poroshkovaya Metallurgiya, No, 4(304), pp. 1–6, April, 1988.     

Ceramic-metallic (TiN-Cu) nanostructured ion-plasma vacuum-arc coatings for cutting hard-alloy tools

The structure and properties of TiN-Cu coatings with a broad range of copper concentrations (C _Cu = 0.6–20 at %), which were fabricated by the ion-plasma vacuum-arc deposition on a TT10K8B hard-alloy tool, including its cutting resistant tests, were investigated. The introduction of copper into the coating composition diminishes crystallites of the nitride phase from 100 to 20 nm. The hardness of coatings increases from 20 to 40 GPa, with an increase in C _Cu to 7–8%. The further increase in the copper content, which is accompanied by diminishing crystallites of the nitride phase, is characterized by a decrease in hardness to 14–15 GPa, which is associated with the influence of soft plastic metal. Resistant cutting tests of steel 35KhGSA of removable multifaceted plates (RMP) with the TiN-Cu coatings indicate that the optimally selected composition (TiN-7-8 at % Cu) increases RMP resistance more than by a factor of 6 and 2.5 as compared with tools without the coating and with the TiN coating deposited according to the basic technology, respectively.     

The energy generation and transmission in compound elastic cylindrical shells with heavy internal fluid loading—from parametric studies to optimization

The methodology of boundary integral equations is applied for analysis and optimization of the power flows in elastic compound cylindrical shells with heavy internal fluid loading. Two generic model problems are solved and the roles of various physical parameters involved in the problem formulation are assessed. It is shown that the efficiency of an optimization procedure heavily relies on a careful parametric study of wave propagation and correct physical interpretation of its results.     

Investigation of the corrosion cracking of steels 12Kh18N10T, 10Kh17N13M3T,and of the imported steel EN58-J under production conditions of primary aliphatic alcohols

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 7, pp. 29–31, July, 1992.