MAX phase carbides and nitrides: Properties for future nuclear power plant in-core applications and neutron transmutation analysis

Abstract

A family of ternary carbides and nitrides, known as MAX phases, combine attractive properties of both ceramics and metals, and has been suggested for potential nuclear reactor applications. The unirradiated materials properties of importance for in-core structural materials and as fuel pellet coatings for several leading MAX phase materials have been summarized from literature. The materials show high mechanical damage tolerance in terms of creep, thermal/mechanical fatigue and fracture resistance, and very good chemical compatibility with select coolants such as molten lead and sodium. Neutron activation has been calculated for commercial purity materials exposed to both idealized fast and thermal reactor neutron spectra for 10, 30, and 60 years of exposure. The specific activities of Ti 3 SiC 2 , Ti 3 AlC 2 , and Ti 2 AlC were compared to those of SiC and Alloy 617, two leading candidate materials for next generation reactor components. The specific activities of MAX phases were similar to SiC and three orders of magnitude less than Alloy 617 after 10-60 years decay for all three activation times in both the fast and thermal spectra. As with SiC, the main radioisotopes after a decay period of 10 years for all three activation times in the MAX phases are tritium and C 14. Neutron irradiation results of Ti 3 SiC 2 , Ti 3 AlC 2 , and Ti 2 AlC experimentally confirmed the neutron transmutation analysis.

Synthesis of the new MAX phase Zr 2 AlC

“…Apart from this economical argument, the fuel cladding materials of next generation (Gen-III+) light water reactors (LWRs) must withstand severe operating conditions where mechanical and thermal loads are combined with high neutron irradiation doses and strongly oxidative or corrosive environments [24]. Based on their superior properties, MAX phases are considered as candidate materials for fuel cladding applications, either in bulk form or as coatings.…”

Roles of silicon-layer in Ti3SiC2 materials response to helium irradiation: New insights from first-principles calculation

“…In addition, this material possesses unusual mechanical properties, such as easy machinability, a high Young's modulus, an ultra-low friction coefficient [2][3][4][5][6][7][8], and nonlinear elasticity in strain cycling, which makes it a potential candidate for practical applications as a high-temperature structural material [9][10][11], damping material [12], self-lubricating material [13], etc. Recently, MAX phases were proposed as candidates in advanced nuclear reactors [14,15] with particular potential applications as fuel coating or cladding material for future fission reactors [16,17]. Several studies have evaluated the irradiation tolerance of MAX phases under high-energy ion irradiation [17][18][19][20].…”

On the interactions of Ti2AlC, Ti3AlC2, Ti3SiC2 and Cr2AlC with silicon carbide and pyrolytic carbon at 1300 °C

“…Recently the MAX phases have been proposed for use in the nuclear industry [18,19]. However, before the MAX phases can even be considered for use in such applications, and to better understand where they would be most judiciously used, much needs to be better understood and quantified.…”