Let Q(J!k) be an imaginary quadratic "eld with discriminant !k and class number h, with kO3, 4, or 8. Let p be a prime such that (~k p )"1. There are integers C, D, unique up to sign, such that 4ph"C2#kD2, p PC. Stickelberger gave a congruence for C modulo p which extends congruences of Gauss, Jacobi, and Eisenstein. Stickelberger also gave a simultaneous congruence for C modulo k, but only for...

The aim of this work was to compare the microstructures 17-4PH martensitic stainless steels (MSSs) obtained by conventional manufacturing (CM), and additive (AM) using laser beam melting (LBM) process. Both materials were studied after same H900 heat treatment. Significant differences in microstructure observed between two MSSs, with a higher austenite content for AM-H900 sample, as compared CM...

Abstract 17-4 PH stainless steel alloy has been widely used in the field of defence industry such as weapon equipment, aerospace, nuclear energy, and so on because its high strength, toughness, temperature resistance, corrosion resistance. In order to meet flexible manufacturing requirements multi-variety small batch complex structure products with lower cost higher efficiency, selective laser-...

(AlCrTiMoV)N high entropy nitride film was prepared on 17-4PH stainless steel substrate using cathodic arc evaporation (CAE). The composition, microstructure, and thermal stability were investigated scanning electron microscopy (SEM), transmission (TEM), X-ray diffraction (XRD). Mechanical properties such as hardness Young’s modulus coating performance against wear erosion also evaluated. resul...

Abstract We fabricated 17-4PH stainless-steel specimens via Fused Filament Fabrication (metal FFF). Then, we studied the effect of varying specimens’ printing angles to bed surface (part orientation) by analyzing tensile test and scanning electron microscopy results. found anisotropy, where printed at 90° exhibited lowest tensile-stress-at-maximum-load 440.15 MPa elongation-at-break 0.83%, comp...