Pinning efficiency of austenite grain boundary by a cubic shaped TiN particle in hot rolled HSLA steel

The Zener coefficient of a cubic shaped particle was modified. Most previous developments of Zener coefficients have been based on the assumption that the particle is spherical. However, some particles have non-spherical geometries, and then a modification of the Zener coefficient that is based on the shape of each particle is needed. In this research, a cubic TiN particle was considered. A Zener coefficient of cubic shape TiN was calculated theoretically with appropriate assumptions. Using a semi-empirical method, the Zener coefficient was also measured. Zener coefficient was strongly dependent on the contact geometry between the grain and the particle.

► Zener coefficient of cubic shaped TiN particle was theoretically derived.
► Zener coefficient depends on contact geometry of TiN particle and grain.
► Calculated Zener coefficient is from 1.76 to 3.51 by changing contact geometry.
► Calculated values have a good agreement with experimental results.