Composite tungsten-thermoplastic
Paweł Skoczylas, Olgierd Goroch, Mieczysław Kaczorowski
Quarterly No. 3, 2010 pages 218-223
DOI:
keywords: composite, mixture tungsten-thermoplastic, tungsten powder, pressing, density, compressive strong
abstract This invastigation are continuation of previously work publicated KOMPOZYTY no. 2/2009. Investigation of manufacturing composite polymer-tungsten powder were presented commercial resin (Epidian 100) and tungsten powders with grain size 0.8, 3.2, 50 m FSSS were used. Mixtures containing 2, 3, 4% of resin were used. Influence of the size tungsten powders and content of the resin on dencity, porosity, compressive strength composite were determined. Through the centuries lead found wide application in various fields of human lives. Lead and its alloys were used as joining components of structure. An unquestioned advantage of lead, from the point of view of its processing is relatively low melting point. Lead is widely used also now in mass manufacture of products. These are car batteries, solders in electronies, weights, core of projectiles (ammunition), etc. Recently, increasing attention has been paid to harmful influence of lead on living organism, and susceptibility of lead to became accumulated in human bodies. Lead can be introduced into an organism simultaneously with food it can be inhaled or absorbed throught the skin. Lead attacks the central nervous system, kidneys, system of ressels and red blood cells. The removed of lead from the organism is a difficult process. Over the last decade lead has been included into the group of 20 most toxic substances. Following this fact, in some scientific centers around the world the research of new materials to substitute lead has been undertaken. Investigation of manufacturing composite polymer-tungsten powder were presented commercial thermoplastic (Owispol 825) and tungsten powders with grain size 0.8, 3.2, 50 m were used. The mixtures contain 3.0; 3.5 and 4.0% weight polystyrene Owispol 825. The mixtures was made by dry mixing method, wet method and in temperatures 220°C. The mixtures was next granulated. Density, porosity, compressive strength composite were examined. Influence of the size tungsten powders and content of polystyrene on density, porosity, compressive strength and homogeneity were determined. The density of the green compact after pressing in room temperature was not useless. Granulated product after moulding of range 20÷130 MPa in temperature 170°C was useful to obtain green compact with density 11.3 Mg/m3. Granulated product with tungsten powder size of 0.8 μm was useless to receive green compact with density 11.3 Mg/m3. The granulate made of tungsten powder with grain size of 50 μm characterized good compressibility. This method anable to receive density composite 11.3 Mg/m3 conteining 96.5% tungsten powder and 3% Owispol 825 under a load 60 MPa. The granulate with tungsten powder size of 3.2 m and 3.5% polistyrene under a load 20 MPa gives parts with density of 11.3 Mg/m3. It has been shown that proposed method, is a good substitute of lead for special applications can be manufactured.