Tribotechnical properties of sintered bronze strengthened by aluminide of Ti–46Al–8Cr

The influence of ultrafine powder Ti–46Al–8Cr intermetellic addition obtained by MASHS on tribotechnical properties of Bro10 sintered bronze has been investigated. The addition of aluminide makes it possible to decrease the instantaneous friction coefficient of sintered bronze under concentrated loading upon friction with 40X hardened steel by 1.2–1.3 times upon continuously increasing loads by two times and to reduce temperature in the friction area by 1.15–1.6 times while increasing the wear resistance by 20 times upon permanent loadings and by 35–40 times upon continuously increasing loading.     

Features of obtaining an effective catalyst for synthesis of carbon nanostructured materials

Abstract

In the present paper, the features of obtaining a metal oxide Fe–Co/Al₂O₃ catalyst for the synthesis of carbon nanostructured materials through thermal decomposition are considered. It was experimentally proved that the temperature and duration of the stage of thermal decomposition of the initial components solution significantly affect the catalyst activity in the synthesis of carbon nanostructured materials by the CVD method. It was found that controlling the mode parameters of the thermal decomposition of the initial components solution of the Fe–Co/Al₂O₃ catalyst, one can not only obtain a catalyst with the required characteristics but also directionally synthesize carbon nanostructured materials over the resulting catalytic systems. During the experiments, rational modes for the implementation of the method for producing catalysts were determined, allowing to form a metal oxide system with a specific surface area of 108?m²/g, the use of which in the synthesis of carbon nanostructured materials leads to the formation of multi-walled carbon nanotubes with an external diameter of 30?nm.     

Correcting the Characteristics of Silicon Photodiodes by Ion Implantation

Semiconductors - The measured electrical parameters of silicon pin photodiodes subjected to the implantation of defect-forming ions and subsequent heat treatment are analyzed, which reveal a new...     

On the Effect the Iron Content on the Tribological Properties of Sintered Tin-iron Bronze

The effect of iron content on the strength and tribological characteristics of sintered tin-iron bronzes has been studied. It has been shown that the porosity has been reduced and the hardness monotonically increased with an increase in the iron content of the material. The strength dependence of the iron content is nonmonotonic, and the maximum strength increase took place at the iron content of 5%. The minimum coefficient of friction, the temperature in the friction zone and wear rate have been observed at iron content of 5–10%. In this case, the micropores and microlacunes have been formed on the friction surfaces that provide better lubricate conditions for the friction surfaces.     

Precursor synthesis and properties of iron and lithium co-doped cadmium oxide

Journal of Electroceramics - Lithium and iron co-doped cadmium oxide Cd0.9(Li1-xFex)0.1O (x?=?0.1, 0.3, 0.5, 0.7) with NaCl structure has been synthesized using formate of the...     

Chemical preparation of samples of dead automobile catalyzers for subsequent determination of platinum, palladium, and rhodium using atomic emission spectrometry with inductively coupled plasma

Systematic studies of different methods for decomposition of samples of dead automobile catalyzers (ACs) on a ceramic base using mixtures of mineral acids and high-temperature alloying with the aim of subsequent determination of platinum, palladium, and rhodium using atomic emission spectrometry with inductively coupled plasma are presented. The behavior of matrix components of dead ACs under the conditions of sample decomposition is investigated. The effect of the results of determining platinum group metals is studied. The relative standard deviation of the results of the analysis performed according to the developed techniques is 11-9% at platinum, palladium, and rhodium concentrations ranging from 0.01 to 0.3%.     

Tribological behavior of sintered tin bronze with additions of alumina and nickel oxide

The tribological characteristics of sintered tin bronze with additions of oxides of aluminum and nickel have been studied. The addition of ultrafine particles of alumina or the mixture of alumina and nickel oxide to sintered tin bronze reduces the coefficient of friction, the temperature in the friction zone and the volume wear rate of the rubbing surfaces. The average coefficient of friction of the material does not change substantially over time. During wear, the chipping of oxide microparticles was observed, which led to a change in the roughness of the working surfaces. The presence of Motor Life Professional additive in oil reduces coefficient of friction, the temperature in the friction zone, and the volume wear rate of rubbing surfaces.     

Effect of Copper Content on Tribological Characteristics of Fe−C−Cu Composites

The paper presents the results of an investigation of the effect of the copper content on the tribological characteristics of Fe?C?Cu composites. It has been shown that the best tribological properties and hardness are shown by material containing 3% copper. In the case of a 10% copper concentration, the wear rate of the composite rises by as much as ten times, while at a 20% concentration, it decreases. It has been proved that the copper concentration significantly affects the formation of friction surface morphology.