Larisa N. Dyachkova

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.

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.

On Some Mechanical Properties and Wear Behavior of Sintered Bronze Based Composites Reinforced with Some Aluminides Microadditives

Abstract In the paper, the changes in some mechanical properties and wear behavior of CuSn10 sintered bronze and MMCs based on this bronze reinforced with composite ultrafine aluminide powders FeAl/15 % Al2O3, NiAl/15 % Al2O3 and Ti-46Al-8Cr are described. It was observed that the presence of aluminides in the MMCs leads to an increase in the hardness, but the flexural strength may increase or decrease depending on the type of aluminide. The presence of aluminides in the MMC reduces the wear rate considerably. It is decreased in the direction of FeAl/15 % Al2O3 → NiAl/15 % Al2O3 → Ti-46Al-8Cr aluminides and for the best MMC composition the advantage is about 20 times. In the MMCs wear process, micro-craters are formed on the contact surface and it is the principal reason of a decrease in the wear rate.

Morphology of worn surfaces of iron–graphite materials sintered or infiltrated with tin bronze

Specific features of the wear of an iron—graphite material with molybdenum disulfide additive produced by compaction followed by sintering or infiltration with tin bronze are studied. It has been found that in the course of friction the lubricant and hard wear particles accumulate in pores on the surface of the sintered material, which leads to the abrasive wear of the counterbody. During the friction of the infiltrated materials, selective mass transfer occurs due to the morphology of the copper phase, and the wear surfaces of these materials have a sponge—capillary structure. The wear resistance of the infiltrated materials is 2.5–3.3 times higher than that of the sintered materials.