Preliminary investigation of manufacture environmentally-friendly composite lead substitute
Paweł Skoczylas, Zbigniew Ludyński, Mieczysław Kaczorowski
Quarterly No. 2, 2009 pages 159-163
DOI:
keywords: composite, mixture tungsten-epoxy, thermal phenomena, pressing, density, compressive strength
abstract Through the centuries lead found wide application in various fields of human lives. Such application can be mentioned as examples: water supply, tanks and pipes, paints bearing, coins. 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 electronics, 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 thought 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. Preliminary investigation of manufacturing composite polymer-tungsten powder were presented commercial resin (Epi-dian 100) and tungsten powders with grain size 0.8, 3.2, 50 μm were used. The resin were dissolved in acetone and next put in tungsten powders. Mixtures containing 2, 3, 4% of resin were fabricate. Dencity, porosity, compressive strength composite were examined. Influence of the size tungsten powders and content of the resin on temperature cure were determined. The density of the green compact after pressing (100, 200, 300, 400 MPa) were from 8.3 to 12.8 Mg/m3. The powder size of 0.8 μm was useless to receive composite with density 11.3 Mg/m3. The granulate made of tungsten powder with grain size of 50μm characterized good compressibility. This method enable to receive dence composite 11.3 Mg/m3 containing 97% tungsten powder and 3% resine under a load 200 MPa. The granulate with tungsten powder size of 3.2 μm and 3% resine under a load 400 MPa gives parts with density of 11.3 Mg/m3. Compacted composite were cured at temperature 170ºC. Process of cured rased compressive strength composite. It has been shown that proposed method, is a good substitute of lead for special applications can be manufactured.