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Quenching experiments are carried out on a dilute Ni‐5 wt% Mn alloy by using both, maximum magnetic susceptibility (χmax)and magnetic coercivity (Hcr). A value of 0.29 eV is determined for the Mn‐vacancy binding energy. A main recovery stage observed after quenching is inferred to the outcome of two mechanisms having opposite effects on χmax and Hcr, namely, the release of vacancies from Mn‐traps formed during quenching and their subsequent agglomeration at deeper traps in complex aggregates at higher annealing temperatures.

Different contents of high abrasion furnace black filler [HAF] and white filler [silica are mixed with ethylene-propylenediene monomer rubber [EPDM] cured by the conventional sulfur system. The thermogravimetric analysis (TGA) characteristics, physico-mechanical properties and swelling measurements of the prepared samples have been investigated. EDAX analyses were done to define the chemical composition of the investigated samples and to locate the dispersion of the fillers and theirs intensity. Comparison of the black and white fillers was performed and it was found that filler incorporation into the rubber matrix was one of the major parameters that enhanced the tensile strength and swelling resistance. The hardness of the investigated samples increased with increasing the filler concentration up to 40/60 phr (part per hundred parts of rubber). This increase can be attributed to greater and more uniform dispersion of filler into the rubber system. Carbon/silica are extensively used in the industry as cheapening filler with high reinforcing effect. Finally, the addition of precipitated silica at the expanse of toxic carbon black (CB) is the main step in decreasing the health risk associated with the presence of CB-filled EPDM composites.

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