Motivated by enrobing processes in manufacturing technology with intelligent coatings, this study analyses the flow of an electroconductive incompressible nanofluid with heat distribution in a boundary layer containing metallic nanoparticles or ferroparticles along an extending cylindrical body with magnetic induction effects. The quasilinear boundary conditions for the partial derivative formulations connecting to the far stream and cylinder wall are converted to ordinary nonlinear derivatives by applying appropriate similarity transformations. The emerging system of derivatives is solved by a stable, efficient spectral relaxation method (SRM). The SRM procedure is benchmarked with special limiting cases in the literature and found to corroborate exceptionally well with other studies in the literature. Here, water is taken as the base liquid containing homogenously suspended nonmagnetic (Nimonic 80a, silicon dioxide [SiO2]) or magnetic nanoparticles (ferric oxide [Fe3O4] and manganese franklinite [Mn–ZnFe2O4]). The influence of all key parameters on the velocity and temperature distributions is displayed in graphs and tables with extensive elucidation. The wall local drag force (skin friction) and local temperature gradient (Nusselt number) are also visualized graphically for various parameters. The rate of convergence of the SRM convergence is compared with that of the successive over‐relaxation method, and it is observed to converge faster. Larger magnetohydrodynamic body force parameter and inverse Prandtl magnetic number induce flow deceleration and enhance temperature. Flow acceleration is computed for SiO2 nonmagnetic nanoparticles, and good heat conduction augmentation is produced with magnetic nanoparticle Fe3O4.