ИСТИНА

MAX-phases are the family of atomically layered compounds with the common Mn+1AXn formula, where M is an early transition metal, A is an A-group element and X is either C or N. MAX-phases are familiar for the characteristic set of properties, combining both metallic and ceramic ones, such as high electric and thermal conductance, elastic stiffness, easy machinability, tolerance to high-temperature corrosion and harsh environments. MAX-phases are being considered for a plethora of practical applications, from chemically stable electrical contacts to protective and shielding coatings and high-temperature applications. One of the most intriguing goals is to obtain stable magnetic MAX-phase that will expand the application field of these materials toward spintronics and other practical uses. This can be possibly done via the chemical doping of existing MAX-phases with magnetic elements. The promising candidate for this purpose - (Cr1-xMnx)2AlC MAX-phase. The ability of this compound to possess tunable magnetic properties, controlled by the variation of the manganese content, is also of the great interest. Recently we have established the protocol to successfully produce phase-pure samples of (Cr1-xMnx)2AlC MAX-phase with dopant concentrations up to 15 at.% which is half times higher than the largest doping level, achieved previously. The protocol requires complex optimization of the exploited synthesis method (arc melting technique) and further purification of the obtained samples via their chemical etching in the powder form. In this work we have performed the complex analysis of the magnetic properties of (Cr1-xMnx)2AlC MAX-phase before and after the chemical purification. As a result, we found out that all the visible magnetic transitions, observed from the studied M vs T dependences, are associated with the secondary phases, appearing during synthesis. In the same time, (Cr1-xMnx)2AlC MAX-phase appeared to be a paramagnet of a mixed type, Langevin and Pauli, in the whole range of manganese concentrations, up to 16 at.%. Both impacts to the composition paramagnetism were studied separately; their dependency on the manganese doping level was also examined. The achieved results are of the great interest for the further work in the field of magnetic MAX-phases in quaternary systems.