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In this work, a comparative analysis of two iron bullets found in The Royal Ammunition Factory of Eugi in Navarra (Spain) was performed. Both bullets presented a spherical shape with a relatively good state of preservation, belonging to the last years of the factory production (1766-1850). Several techniques such as microhardness, X-ray fluorescence (XRF), light (LM) and scanning electron microscopy (SEM), optical mission spectroscopy (OES) and energy dispersive X-ray spectroscopy (EDX) analysis were used in order to identify the manufacturing process of the two bullets. The analyses of the microstructures carried out by LM and SEM showed that one bullet was composed of white cast iron with a pearlitic matrix, steadite and graphite; while the other was composed of grey cast iron with a pearlitic matrix, graphite and a low amount of steadite. The chemical analysis of the bullets carried out by OES indicated significant differences in the amount of silicon and phosphorous. The variation in silicon content could suggest that the foundry temperature under oxidizing environment varied during the casting. The SEM and EDX analyses showed both bullets had manganese sulphide inclusions but only one of the bullets exhibited titanium and vanadium inclusions. The microhardness analyses carried out revealed Vickers hardness differences along the diameter. This variation could be explained by the differences in cooling rate along the diameter. Based on the physical characteristics of the bullets and on the obtained results, it can be concluded that one of the bullets could have been used as a grapeshot projectile and the other one as a bullet for ribauldequins. In addition, calcined ore and slag found in this factory were also analysed. The variation found in their chemical composition corroborated that the foundry temperature employed during the manufacturing process was low, the slag being enriched in Si, Al and Mn elements.

In this work, a comparative analysis of two iron bullets found in The Royal Ammunition Factory of Eugi in Navarra (Spain) was performed. Both bullets presented a spherical shape with a relatively good state of preservation, belonging to the last years of the factory production (1766-1850). Several techniques such as microhardness, X-ray fluorescence (XRF), light (LM) and scanning electron microscopy (SEM), optical mission spectroscopy (OES) and energy dispersive X-ray spectroscopy (EDX) analysis were used in order to identify the manufacturing process of the two bullets. The analyses of the microstructures carried out by LM and SEM showed that one bullet was composed of white cast iron with a pearlitic matrix, steadite and graphite; while the other was composed of grey cast iron with a pearlitic matrix, graphite and a low amount of steadite. The chemical analysis of the bullets carried out by OES indicated significant differences in the amount of silicon and phosphorous. The variation in silicon content could suggest that the foundry temperature under oxidizing environment varied during the casting. The SEM and EDX analyses showed both bullets had manganese sulphide inclusions but only one of the bullets exhibited titanium and vanadium inclusions. The microhardness analyses carried out revealed Vickers hardness differences along the diameter. This variation could be explained by the differences in cooling rate along the diameter. Based on the physical characteristics of the bullets and on the obtained results, it can be concluded that one of the bullets could have been used as a grapeshot projectile and the other one as a bullet for ribauldequins. In addition, calcined ore and slag found in this factory were also analysed. The variation found in their chemical composition corroborated that the foundry temperature employed during the manufacturing process was low, the slag being enriched in Si, Al and Mn elements. [ABSTRACT FROM AUTHOR]

The present study compares the formation mechanism of two common defects in gray iron castings, sweat phosphide in a new form and expansion scab. Normally, when a solid crust occurs on the surface of gray iron castings, it is called 'a scab.' In this study, we compared these two defects by means of standard metallography procedure and scanning electron microscopy. The result indicates that a scab caused by sand expansion is accompanied by sand particles beneath the solid crust and its microstructure is identical with the casting, while there are no sand particles beneath the sweat phosphide and its microstructure differs from casting. [ABSTRACT FROM AUTHOR]

In reciprocating sliding, it is not yet specified the difference of effects between higher frequency and lower frequency on friction and wear under a given sliding velocity. In the study of cast irons, focus seems to be mainly on behaviors of graphite flakes. In this report, sliding characteristics of marine cylinder liner materials were studied on an SRV tester in terms of contact frequency by varying frequency and stroke under a given sliding velocity in base oils and oils with EP-additives, DBDS ( Dibenzyl Disulphide ). In higher contact frequency, or a combination of higher frequency and a smaller stroke, friction was observed to become higher than at lower frequency under severe lubricating conditions. However, run-in process was promoted under higher contact frequency with increase in viscosity and sliding velocity. Hard-phase particles, steadite, showed a tendency to chip from rubbed surfaces because of higher contact frequency, causing higher friction. The effects of frequency and stroke in base oils reflected on those of EP-additives. In DBDS-added oil, higher friction under higher contact frequency was also observed for severe lubricating conditions. Larger value of S/O ratio was confirmed by X-ray analysis of worn surfaces under higher friction. The ratio of S/O ratio decreased to less than one with improved lubricating conditions.

The old gray cast iron for water supply pipes in Yokohama City which was made in the UK in 1887 is highly corrosion resistant. The corrosion behavior of the old gray cast iron in soils was studied. For comparison, a gray cast iron used for modern pipes, a spheroidal graphite cast iron, and a carbon steel were tested. The corrosion potentials and corrosion rates were measured. The corrosion products and the base metals were analyzed by X-ray diffractometry and energy dispersion spectroscopy. The corrosion rate of the gray cast iron made in the UK in 1887 was lower than those of the others. The gray cast iron contains a large amount of steadite, which is a ternary eutectic (γ-Fe, Fe3C, and Fe3P). The network structure of steadite enclosed the corrosion products and decreased the corrosion rate. [ABSTRACT FROM AUTHOR]

Abstract: This research investigates the effect of phosphorus as an alloying element on microstructure, eutectic temperature, hardness and mechanical properties of gray cast iron. Five different amounts of phosphorous (0.5, 1, 1.5, 2 and 2.5wt%) have been added. Results show that increasing phosphorous from 0.45 to 2.58% in gray cast iron increases the amount of eutectic phosphide from 4.7 to 17.81%, weakens mechanical properties (tensile strength reduced from 297.5 to 184.1MPa, impact strength from 4.3 to 2.7J), increases hardness from 215.43 to 249.38 and lowers the eutectic temperature from 1139.7 to 1102.5°C. [Copyright &y& Elsevier]