الملخص

Abstract In this research, we prepared a eutectic ternary alloy from (Pb-Sn-Zn) metals under normal pressure. We investigated some of the physical properties of the alloy and their elements, which are thermal properties (melting point by using a thermal analysis system, specific heat by using mixed method, thermal expansion by using a system made in our laboroutary, mechanical properties (hardness test by using Rockwell manner depending on (E18-84) standard from ASTM ,fatigue strength by using (BS 3518) standard, also we examined specific gravity depending on (C20-83) standard from ASTM. the result of alloy melting point are approximately similar to that issued in the literary with a little difference because of the alloy suffering from high cooling rate in the thermal analysis system. The result of specific heat is high somewhat because of the many problems in the mixing method. The result of thermal expansion is approximately identical to the standard value in the literary because of the high resolution of the system which are (1 µm). The result of mechanical properties showed the hardness value similar to binary eutectic alloy(Pb-Sn),and increases in the hardness value after the heat treatment in the (57-90) and decreases with increasing heat treatment duration and temperature. The result of fatigue strength showed the absence of fatigue limits and we can't get a precise result because of synergistic many variables in the test which are geometrical shape of the specimen, frequency and the residual stress. specific gravity results show approximately identical with standard value in the literary which lead to the perfect alloy casting and absence of casting defect.