Features for formation of solid alloys of chromium carbide and titanium powder mixtures by explosion energy

Кузьмин

et al. 2019

MSF

The article reports findings on theoretically-calculated data and experimental results obtained with scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy methods of the analysis of hard alloys produced by the explosive compaction of the Cr3C2 chromium carbide powders with titanium, first in the original condition and then after heating to 1200 °C. It was established that when heated to 600 °С the phase composition of hard alloys does not change and corresponds to the composition of the original components of the powder mixture. When the heating temperature was increased to 650 °С, new fine powder fractions emerged at the “chromium carbide – titanium” interface. At the temperature of 700 °С two separate diffusion layers emerged and grew in the opposite directions. Due to this growth the source phases in the alloy fully disappeared at 1200 °С and two equilibrium phases were formed.

Section: Methodsmentioning

confidence: 99%

The Effect of Heating on Phase Composition of the Cr3C2- Ti System Hard Alloys Fabricated by the Explosive Compaction of Powder Mixtures

Кузьмин

et al. 2019

MSF

“…Chromium carbide (Cr 3 C 2 ) was chosen as the alloy base because it is the most promising carbide for operation in oxidizing medium at temperatures of 300-400°C [8,9,10], which correspond to the conditions typically achieved during the operation of friction assemblies of pumps for the transfer of overheated distillate. Titanium was used as the metallic binder due to its low acoustic stiffness, which ensures good compressibility of the powder mixture during explosive processing [11]. The binder content in the powder mixtures was 14, 22, 31, and 40 mass %, which corresponds to 20, 30, 40 and 50 vol.…”

Section: Methodsmentioning

confidence: 99%

Formation of Hard Alloys of Chromium Carbide and Titanium Powder Mixtures by Explosive Pressing

Кузьмин

et al. 2016

KEM

The production of a new type of hard alloys by explosive compaction of chromium carbide (Cr3C2) and titanium powder mixtures was investigated. The phase composition of the fabricated alloys was studied using scanning electron probe microanalysis. The chemical composition of the alloy components does not change, and no redistribution of the elements was observed. The formation characteristics of the interfaces between the material components during shock wave processing were investigated using electron microscopy. The explosion compaction of high melting carbide and metal powder mixtures results in the formation of consolidated hard alloys during the compaction stage.

“…We studied alloys containing 20, 30, 40, and 50 vol. % titanium binder, with the maximum hardness HV and density close to that of the monolithic material [5]. Tests were conducted on a MI-1M friction machine in the "finger-ring" configuration with incision (Fig.…”

Section: Methodsmentioning

confidence: 99%

“…Slip bearings operating in contact with silicified graphite, in the presence of water, are currently manufactured from alloys of chromium carbide (Cr 3 C 2 ) with nickel or Nichrome alloy obtained by pressing and sintering [2,3,4]. Sintering may be eliminated if the nickel is replaced by titanium and explosive loading is employed [5]. By this means the production of hard alloy also may be combined with its application as a coating to the working surfaces of blanks for frictional systems [6,7,8,9].…”

Section: Introductionmentioning

confidence: 99%

The Wear-Resistance and Antifrictional Properties of Hard Alloys of Chromium Carbide with Titanium Produced by the Explosive Compaction of Powders

Тупицин

et al. 2016

KEM

The tribological characteristics of the Cr3С2–Ti system hard alloys produced by the explosive compaction of powders containing 20, 30, 40, and 50 vol. % of the titanium binder are investigated. The general approach to selecting the optimal structure and properties of wear-resistant hard alloys for manufacturing the slider bearing parts working in conjunction with silicified graphite under water lubrication conditions is formulated. It is shown that, to attain the highest antifriction characteristics and minimal wear of the friction unit, the alloy should have the maximally possible hardness with the minimally admissible specific volume of a carbide phase in the material structure. It is established that such alloys have higher antifriction characteristics and wear resistance than silicified graphite and the Cr3C2–20% Ni-type materials produced by conventional methods.