Effect of surface roughness and surface hardening of 45 steel on the tribotechnical properties of antifriction friction pairs based on iron

Powder Metallurgy and Metal Ceramics -     

Effect of boronizing on the structure and antifriction properties of a bronze-cast iron composite material

Conclusions The boronizing of a bronze -cast iron composite material with a macroheterogeneous structure results in the formation of a discrete boride surface composed of bronze fields and boride zones at sites occupied by cast iron particles. The chemicothermal treatment investigated decreases the coefficient of dry friction of the material from 0.6 to 0.35 and increases its load-carrying capacity from 6 to 18 MPa. Rubbing generates on the material secondary film structures constituting mixtures of bronze and iron oxide and boride particles.Translated from Poroshkovaya Metallurgiya, No. 9 (225), pp. 38–42, September, 1981.     

New self-lubricating antifriction materials based on titanium nitride

Tribological properties of powder composite materials of the skeletal and matrix types are studie under conditions of dry friction with rates up to 10 m/sec in air in pair with steels. Titanium nitride is used in order to obtain skeletons, and the matrix is polytetrafluoroethylene (PTFE). It is established that the tribological properties depend on the type of structure. In level of wear resistance materials of the skeletal type surpass by a factor of 1.5 the original compact materials, and filled PTFE by a factor of eight to nine. Use of PTFE makes it possible to improve markedly the tribological properties of composite materials based on titanium nitride and to reduce significantly (up to 40%) the weight of friction assemblies.     

渗铜剂成分对烧结钢渗铜性能的影响

采用纯Cu粉、Cu-2Zn粉、Cu-2Fe粉、Cu-2Zn-2Fe粉等4种不同成分的渗铜剂,以Fe-Cu-C烧结钢为基体,在1 120～1 150℃、保温30 min工艺下渗铜,研究不同成分渗铜剂的熔渗性能及其对渗铜烧结钢力学性能的影响。结果表明:同其它3种渗铜剂相比,Cu-2Zn-2Fe渗铜剂渗铜性能最好,烧结钢渗铜后表面质量均匀一致、无溶蚀现象;上下表面硬度基本一致,较未渗铜烧结钢提高了约60%;4种渗铜剂渗铜的烧结钢冲击韧性为13.7～14.0 J/cm2,较未渗铜的提高2倍以上;在渗铜剂中,Fe元素可以降低渗铜剂熔体活性、增加黏度;Zn元素可以降低渗铜剂熔体黏度、增加其活性。     

Effect of graphite content on the antifriction properties of metallographite materials

Summary Metallographite materials containing not more than 50 vol.% graphite can be used for rubbing-friction applications at high velocities in conditions of limited lubrication. Further increase in the graphite content sharply reduces the strength of the material.With increase in the friction rate and loading, the coefficient of friction diminishes. This tendency occurs with increase in the graphite content in the structure, when a reduction in the strength of the material contributes to an increase in the wear and the growth in friction coefficient owing to the development of dispersion in the material being rubbed.The metallographite materials investigated, containing graphite in the range 50–90 vol.% under dry friction conditions,have a high coefficient of friction (of the order of 0.22–0.40) which means that they cannot be recommended as antifriction materials.In the case of operation with lubricant the metallographite materials can operate as antifriction materials with friction coefficients of 0.03–0.06 at velocities of up to 50 m/sec and with loads of up to 3.3–3.8 kgm/cm² · sec (PV=165–195 kgm/cm² · sec).     

Special traits of the structure formation of alloyed antifriction materials

Translated from Poroshkovaya Metallurgiya, No. 11(359), pp. 61–66, November, 1992.     

Structure and properties of nichrome-boron nitride powder materials for tribotechnical pairs

Translated from Poroshkovaya Metallurgiya, No. 6(330), pp. 47–51, June, 1990.     

真空烧结温度对铜基减磨材料性能的影响

以铜粉、锡粉、铅粉等为原料,采用“压制-烧结”工艺制备了铜基减磨材料,烧结采用真空无压烧结和还原气氛保护烧结两种工艺方法.运用对比试验的方法,探讨了真空无压烧结工艺中不同烧结温度对铜基减磨材料烧结体性能的影响.结果表明:真空烧结工艺与还原气氛保护烧结工艺相比,相同的烧结温度下材料的孔隙度、抗拉强度、抗压强度和硬度变化不...     

Compaction, structure formation, and properties of materials based on boron carbide

The effect of adding aluminum and titanium on the compactibility kinetics, structure, and properties of materials in the systems B₄C-Al and B₄C-(Ti-Al) is studied. The micromechanical properties (microhardness, microbrittleness, microstrength, and crack resistance factor (K_1c) of composite materials are determined. The influence of high pressure on the compactibility, structure, and properties of B₄C-based materials with additions of titanium and aluminum is investigated.     

Structurization in sintering of antifriction powder materials based on iron-copper alloys

The paper studies the contact interaction of the components in powders Fe-(Cu + Sn), Fe-(Cu + Sn + P + Pb), and Fe + B-(Cu + Sn + P + Pb) during sintering in hydrogen at 920 °C. It is shown that this interaction is responsible for the formation of both the interphase boundary and the general structure that defines the performance characteristics of an antifriction material. The interface and the phase and chemical composition of the products of interaction are examined. It is established that the powder composition Fe + Cu + Sn + P + B + Pb sintered in hydrogen at 920 °C is a microheterogeneous material whose matrix, which takes up the major load during friction, includes two phases: one based on iron alloyed with boron (Fe₂B), copper, tin, and phosphorus and the other based on copper including tin in the form of α-solid solution, phosphorus in the form of Cu₃P, and iron. Lead uniformly distributed over the matrix volume is the antifriction component of the material.     

Pb在快凝Al-Si基减摩材料中的作用

研究AJ-Si基减摩材料中Pb含量与材料力学性能和摩擦磨损特性的关系，分析了材料的微观组织，结果表明，Pb能够提高减摩性能，改善材料的摩擦磨损特性。     

Influence of the content and dimensions of the graphite particles on the structure and tribotechnical characteristics of copper-graphite materials

Conclusions The copper-base material containing 10% type S-1 graphite possesses better antifriction properties in high velocity sliding friction than pure copper or composites with additions of coarse-grained type GÉ-4 graphite.Translated from Poroshkovaya Metallurgiya, No. 9(285), pp. 84–90, July, 1986.