The wear behaviour was investigated of heat treated Hadfield austenitic manganese steel (HAMnS). The wear test was carried out using spin on disc apparatus under different loading loads and speed conditions. A scanning electron microscopy (SEM), an X-ray diffractometer and micro-hardness testing machines were used for examining the morphology, compositions and to measure the hardness of the manganese steel, respectively. The results of the wear test showed that the sliding speed-time interactions effect gave the most significant effect on the austenitic manganese steel. The solution heat treatment programme increased the wear resistance of the alloy steel under increasing load, speed and time. The as-cast microstructure was characterized by heterogeneously dispersed chromium carbides second phase particle, and was responsible for the observed non-uniform wear rate. In regard to the solution heat treated HAMnS, the segregated carbides were dissolved at 1050 °C and uniformly dispersed within the matrix of its microstructure after rapid water quenching to room temperature. This later development was responsible for the uniform and improved wear resistance of the manganese steel casting. This work demonstrated significantly that there is a direct relationship between the second phase carbides, their distribution and the wear rate pattern of HAMnS casting.

Variations in haematological and serum biochemical indices among White Fulani bulls, Ouda rams and West African Dwarf (WAD) bucks were studied. Ten each of mature bulls, rams and bucks were used for the experiment. Blood was sampled from all the animals and analysed for haematology and serum was separated for serum biochemical analysis. The result showed that species had effect on some haematological and serum biochemical indices of White Fulani bulls, Ouda rams and WAD bucks. Packed cell volume, haemoglobin, white blood cells, red blood cells, monocytes and eosinophils were not significantly different among the species, while platelets, lymphocytes, and neutrophils counts were significantly influenced by specie differences. Platelets was significantly (p<0.05) lower in rams (93.20×103 /µL) than in bulls (136.00×103 /µL) and bucks (141.90×103 /µL). Lymphocytes and neutrophils count was significantly (p<0.05) influenced by species differences. Serum biochemical parameters showed that there was no significant difference in the mean values for albumin, glucose, cholesterol, urea and Aspartate amino transferase, while the values obtained for total protein, creatinine and Alanine amino transferase (ALT) were significantly (p<0.05) different among the animal species. Total protein (7.21±0.52 g/dL) and creatinine (1.21±0.19 mg/dL) were significantly (p<0.05) higher in bucks than other species. The ALT was also higher (p<0.05) in bucks (20.83 iu/L) than in rams (7.59 iu/L) and bulls (6.27 iu/L). This study suggests that the effect of specie of an animal influences blood indices. The values obtained in this study can be used as references for haematological and serum biochemical assessment of indigenous male cattle, sheep and goat in Nigeria.

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Corrosion of metals is a common