B4C-Al Composites Fabricated by the Powder Metallurgy Process

Ling Zhang, Jianmin Shi, Chunlei Shen, Xiaosong Zhou, Shuming Peng, Xinggui Long
2017 Applied Sciences  
Featured Application: Neutron absorber materials are used in spent-fuel storage racks, storage, and transportation casks to control the reactivity of spent nuclear fuel, allowing the storage and shipment of spent fuel at maximum packing density. Due to the large thermal neutron absorption cross-section of the nuclide B-10 and the excellent mechanical performance of aluminum, B 4 C-Al composites have the potential to serve as the neutron absorber as well as the structural function in fuel racks.
more » ... tion in fuel racks. This work provides an efficient method to fabricate the homogeneously mixed B 4 C-Al composites with superior yield and tensile strength. Abstract: Due to the large thermal neutron absorption cross section of 10 B, B 4 C-Al composites have been used as neutron absorbing materials in nuclear industries, which can offer not only good neutron shielding performance but also excellent mechanical properties. The distribution of B 4 C particles affects the mechanical performance and efficiency of the thermal neutron absorption of the composite materials. In this study, 15 wt % B 4 C-Al and 20 wt % B 4 C-Al composites were prepared using a powder metallurgy process, i.e., ball milling followed by pressing, sintering, hot-extrusion, and hot-rolling. The yield and tensile strengths of the composites were markedly increased with an increase in the milling energy and the percentages of B 4 C particles. Microstructure analysis and neutron radiography revealed that the high-energy ball milling induced the homogeneous distribution of B 4 C particles in the Al matrix and good bonding between the Al matrix and the B 4 C particles. The load transfer ability and mechanical properties of the composites were consequently improved. The results showed the high-energy ball milling process is an appropriate fabrication procedure to prevent the agglomeration of the reinforcement particles even if the matrix to reinforcement particle size ratio was nearly 10.
doi:10.3390/app7101009 fatcat:5h3gwucgq5ef7knsf6odn5l64a