Effect of degassing parameters on sinterability of Al/B4C powder mixture

• Published in: Powder metallurgy Vol. 58; no. 1; pp. 36 - 40
• Main Authors: Asghar, Z., Zahid, G. H., Rafi-ud-Din, Ahmad, E., Mehmood, M., Badshah, S.
• Format: Journal Article
• Language: English
• Published: London, England Taylor & Francis 01.03.2015; SAGE Publications
• Subjects: Al/B; C composite; Degassing; Hardness; Microstructure; Sintering; Degassing; Microstructure; Hardness; Al/B4C composite; Sintering
• ISSN: 0032-5899; 1743-2901
• DOI: 10.1179/1743290114Y.0000000097

The 6061-Al powder was degassed under vacuum, argon and hydrogen before mixing with 5 mass-%B 4 C particles. After compaction, the supersolidus liquid phase sintering was performed at 630°C under high purity argon and nitrogen atmosphere. The purpose of this experimental plan was to study the effect of different degassing and sintering environments on the compressibility and sinterability of Al/B 4 C composites. The efficacy of degassing condition in-terms of sintered density is in the order of hydrogen, argon and vacuum (highest). Al/B 4 C composite sintered under argon atmosphere after vacuum degassing showed ∼8% higher sintered density as compared to the sample with similar condition except degassing. Al/B 4 C composite sintered under N 2 atmosphere without degassing showed ∼89% density and 65 HRB while the composite sintered under N 2 atmosphere after degassing in vacuum showed ∼98% density and 89 HRB with faded boundaries between 6061-Al particles in the microstructure.