Characterization of tungsten-nickel-iron heavy alloy in relation with impact strength

This paper reports on the relationship between impact strength and characteristics of heavy metal (W-4.4 wt%Ni-2.2 wt%Fe) that was examined experimentally. Two kinds of materials were compared by means of impact tests, micro-auger analyses and SIMS. The impact strengths were 7.3 and 5.7 joule/cm2 respectively. Micro-sugar analyses revealed that the matrix phase of the heavy metal was composed of Ni, Fe and W and that high impact resistance material contained 40 to 65 at% W while low impact resistance material contained about 28 at% of W. SIMS analyses were conducted on both flat face and fractured face of specimens. Contaminants such as oxygen, sulfur, aluminum and so on were detected. In the two dimensional scanning analyses on the flat surface of a specimen, the contaminants were found to be not uniform but dispersed in the matrix. In addition, the investigation of fractured faces showed that high impact resistance material had less contamination on the fractured face than low impact resistance material