The effect of boron and titanium addition on the behavior of steel alloys of base composition AISI304 as a nuclear radiation shielding material

Hafez, Shaimaa; El-Kameesy, Samir; Eissa, Mamdouh; Elshazly, Raed; ELFAWKHRY, Mohamed; Saed, Aly

doi:10.21608/ajnsa.2019.5818.1131

The effect of boron and titanium addition on the behavior of steel alloys of base composition AISI304 as a nuclear radiation shielding material

Document Type : Original Article

Authors

¹ Physics Department, Faculty of Science, Ain Shams University

² Professor of Steel Technology, CMDRI

³ Physics Department, Faculty of Science, Al-Azhar University

⁴ Steel Technology Department, Central Metallurgical Research and Development Institute (CMRDI)

⁵ Nuclear Power Stations Department, Faculty of Engineering, Egyptian Russian University

10.21608/ajnsa.2019.5818.1131

Abstract

Borated stainless steel alloys are candidate neutron absorber materials for criticality control in disposal containers or dry storage canisters. Type 304 borated stainless steels are similar to conventional Type 304 stainless steels except that they contain a boron addition, which imparts a much higher thermal neutron absorption cross section than other austenitic stainless steels. Three grades of steel alloys with base composition of AISI304 (SS304Ti, SS304B and SS304TiB) were modified and produced using 30 kg pilot plant medium frequency induction furnace at the same conditions. The macroscopic-cross sections for neutrons higher than 10 keV, slow, and total slow neutrons were measured using 241Am-Be neutron source for the produced samples. The developed samples were found to have higher cross sections for neutrons higher than 10 keV, slow, and total slow neutrons than SS304. Additionally, gamma ray shielding properties were measured for several gamma ray energies that emitted from 232Th radioactive source. Among the investigated steels, the lowest corrosion rate was found in the modified steel containing B. Samples of the properly treated steels were subjected to microstructure observation, hardness, tensile and impact testing. The microstructure observation revealed an austenitic phase in all investigated steel alloys and a very large number of twins in the optical micrographs of the investigated samples. The strengthening effect of B or Ti and B is to great extent the reason of the solution hardening and precipitation strengthening effects of these elements as these elements are strong carbide or nitride formers.

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