Selecting a Method for the Manufacture of Porous Powder Filter Products

The article considers three methods of increasing the distribution uniformity of properties over the filtration area of powder filter materials at different stages of their manufacturing. It is shown that granulation of metal powders with a pore former increases the uniformity of permeability distribution over the filtration area by a factor of 2.3–3.5. Dry radial isostatic pressing ensures high distribution uniformity of properties, while the coefficient of variation of local permeability does not exceed 0.17. Radial compression allows increasing the uniformity of permeability distribution over the filtration area by 15 ... 22 % compared to that for the original powder filter materials. The selection of the method used in practice is determined by the shape, size and properties of the manufactured products and initial powders. The considered methods can be used in petrochemical engineering for the manufacture of porous powder products for filtering purposes, used to trap catalyst particles, filters for fine and coarse fuel and oil purification.

Studies on properties of Novel natural disintegrant after processing of Spray dried and Freez dried technique

Natural disintegrant are widely used in the development of mouth dissolving tablets and other formulation because of easily available, low cost and rapide onset of action in the mouth dissolving tablet and it enhance the bioavalaibility and disintegration properties as comparaed to synthetic polymer. But aftrer freeze drying and spray drying technique the properties of dsintegrant is increases because its improve the bulkiness and flow property of a powder such as bulk density, tapped density, angle of repose, hausner raio, carrs index etc. by freeze drying the powder are dried and thereby increase the dissolution and disintegration time and highly porous powder is produced by spray drying technique.

RESEARCH OF THE TECHNOLOGY OF OPENING HOLES IN COMPACT AND POWDER MATERIALS

This article is devoted to one of the important problems of mechanical engineering, including processing by cutting and deploying in sintered antifriction powder material in optimal modes with maximum performance. The study was conducted for small diameter cylindrical bushings. Processing of bushings was carried out by reamers from high-speed and carbide tools on materials from porous powder and cast iron. It is established that the temperature of the tools should not exceed the permissible upper limits, for pressing the bushings, it is necessary to use planting with small strains in the cold state. Keywords: engine valve, bushing, powder material, cast iron, reamer, cold pressing.

The Use of Transient Liquid Phases in Powder Metallurgy

Liquid phase sintering is most widely known in its variant „persistent liquid phase sintering“, in which case the liquid phase is present in constant quantity during the entire isothermal period. There is however also the variant „transient liquid phase“, the melt being present only for a short period in the first stage of sintering and then solidifying through diffusional processes. In this presentation, the preconditions for both variants are presented, in particular with regard to the starting materials. The benefits of transient liquid phases are described, both for sintering – to accelerate material transport, contact formation and microstructural homogenization compared to standard solid state sintering – and for transient liquid phase bonding, a brazing variant which is an attractive method for joining porous powder compacts. Both techniques are highly useful in particular for ferrous powder metallurgy precision components, etc.

Investigation of the Composition, Structure and Properties of New Porous Powder Friction Coatings Obtained by Plasma Sputtering

The paper investigates processes of composition selection, structure formation and properties of new porous powder friction materials based on molybdenum (Mo), on aluminum-iron bronze (БpAЖ(SiC)) or steel (40X13) obtained by plasma spraying. The study can be used in the frictional devices of transmissions of tracked vehicles with a high specific power to increase the tribotechnical, operational and technological characteristics.

Сrystalline microcone coatings on titanium sponge.

For the first time it was shown how to obtain microcone-shaped TiO2structures by means of anodizing of porous powder materials made of titanium sponge. It was established that during anodizing in 10 %Н2SO4+ 0,15 % HF electrolyte along with the growth of the X-ray amorphous nanoporous TiO2film a set of microcones with anatase crystalline structure is formed on the surface of titanium sponge powder particles. Microcones (height is up to 7m, base diameter is up to 5m) consist of multilayer nanoscale structures. Such structures are promising for the manufacture of new nanomaterials for catalytic and sensor devices.