Investigation of the residual stresses effect on the magnetic properties of CuO nanoparticles synthesized in a low-pressure arc discharge plasma

•We studied the patterns of formation of residual stresses in copper oxide nanoparticles.•We studied the relationship of the residual stresses and the magnetization of nanoparticles.•We detect the magnetic behavior of CuO nanoparticles similar to other ferromagnetic nanoparticle systems. The laws governing the formation of residual stresses in copper oxide nanoparticles in the process of their direct plasma-chemical synthesis in a low-pressure arc discharge plasma are studied. Correlation dependences of the residual stress and the magnetization of nanoparticles on the pressure of the gas mixture of 10% O2 + 90% Ar are presented. The problems associated with the bifurcation of the magnetization curves during cooling in zero (ZFC) and non-zero (FC) magnetic field, non-equilibrium behavior, relaxation of magnetization and magnetic viscosity of the obtained CuO nanoparticles are discussed.