The Effect of Bi on the Selective Oxide Formation on CMnSi TRIP Steel

Insight into selective oxidation of dual‐phase steel after annealing in pure H2 atmosphere at different heating rates and temperatures

“…The segregation and oxidation of alloying elements on the surface are very complex. And they are often considered to be closely related to the following factors: Annealing parameters (temperature, heating rate, annealing atmosphere, and annealing time), alloying elements, and the matrix microstructure as well as its surface morphology . The characteristics most relevant to this study are temperature, heating rate, and high water pressure.…”

“…It has been reported that reaction rates generally increase with increasing temperature . According to the Wagner theory for parabolic kinetics, the rate of oxide growth is directly proportional to the external diffusion coefficient and temperature of the alloying elements.…”

“…And they are often considered to be closely related to the following factors: Annealing parameters (temperature, heating rate, annealing atmosphere, [12,13] and annealing time), alloying elements, [14] and the matrix microstructure as well as its surface morphology. [15,16] The characteristics most relevant to this study are temperature, heating rate, and high water pressure. In our previous works, it has been shown that raising the atmospheric dew point increases the surface oxygen concentration and the flux of oxygen into the steel, promoting the occurrence of internal oxidation.…”

“…It has been reported that reaction rates generally increase with increasing temperature. [15,20,21] According to the Wagner theory for parabolic kinetics, [17] the rate of oxide growth is directly proportional to the external diffusion coefficient and temperature of the alloying elements. It has been reported by Van de Putte et al [21] that there is almost no oxidation of the surface at low temperatures.…”

Continuous Hot‐Dip Galvanizing of Medium‐Manganese Third‐Generation Advanced High‐Strength Steels

“…This oxide morphology was achieved by using a higher process atmosphere pO 2 to suppress external oxidation and promote internal oxidation. The same authors also employed a surface active alloying element concept from electrical steels, [40][41][42][43] subsequently employed for a series of low alloy Si/Mn TRIP-assisted steels, [44][45][46][47] to reduce selective oxidation kinetics and facilitate reactive wetting. To this end, Pourmajidian et al [25,39] showed that a 0.05 wt% addition of Sn to their reference 6 wt% Mn substrate retarded oxidation kinetics, and the resulting surfaces were more easily reactively wetted due to the smaller and more discrete oxide nodule morphology.…”