This steel sample was “SurfMet” Processed for a scanning electron micrograph (SEM) study to determine alloy diffusion. Examination included an X-ray energy analysis of the alloying material and several line scans over the sample cross-section in an effort to detect alloy diffusion. Examination of the micrograph discloses three different zone areas.
Alloyed “skin”; the addition of a superior, harder material and dimensional growth. The total area consists of an amorphous (non directional grain formation) structure formed above the original plane.
Interface zone just below the original surface plane; a mixture of crystalline and amorphous structures as wells as diffusion of Tungsten Carbide in the Fe base material.
Area not affected by the treatment; 100% crystalline structure and the greatest percentage of Fe.
The (SEM) Study Concluded
The hard metal alloyed “skin” was identified by x-ray fluorescence spectroscopy to be an alloy of WC (Tungsten Carbide or W for Wolfram). Several x-ray line scans over the sample cross-section indicated a diffusion of Fe into the W alloy and a diffusion of the W alloy below the original surface plane of Fe material. The alloyed “skin” exhibits excellent uniformity, density, and diffusion. A second alloying occurred above and below the original surface plane which also became an integral part of the total mass and therefore not a coating.