Institute of Physics of Materials AS CR, v. v. i. > Projects > Strength, embrittlement and magnetism of clean and impurity-segregated grain boundaries in metallic materials

Strength, embrittlement and magnetism of clean and impurity-segregated grain boundaries in metallic materials

Investigatorprof. RNDr. Mojmír Šob, DrSc.
Number of ProjectGAP108-12-0311
AgencyAkademie věd České republiky
Duration2011-12-31 - 2015-12-30

The goal of the proposed research is to advance our fundamental understanding of structure, magnetism and embrittlement of impurity-segregated grain boundaries (GB) in ferromagnetic Fe, Co and Ni. Central topic of the proposed research is to determine the preferred segregation sites of 12 sp-elements from the 13th-16th group and the 3rd, 4th and 5th period (Al, Si, P, S, Ga, Ge, As, Se, In, Sn, Sb and Te) at the impurity- decorated GBs, their segregation enthalpies and strengthening/embrittling energies with their decomposition into the chemical and mechanical components. Also, at the impurity-decorated GBs and surfaces we will look for magnetically dead layers which are important in materials for spintronics. It may be expected that the results will be important for development of new generation of nickel-based superalloys.


Černý M., Šesták P., Řehák P., Všianská M., Šob M.: Ab initio tensile tests of grain boundaries in the fcc crystals of Ni and Co with segregated sp-impurities. Mater. Sci. Eng. A 669 (2016) 218-225


Pokluda J., Černý M., Šob M., Umeno Y.: Ab initio calculations of mechanical properties: Methods and applications. Prog. Mater. Sci. 58 (2015) 43-49

Řehák P., Černý M., Šob M.: Mechanical stability of Ni and Ir under hydrostatic and uniaxial loading. Model. Simul. Mater. Sci. Eng. 23 (2015) 055010


Lejček P., Šob M.: An analysis of segregation-induced changes in grain boundary cohesion in bcc iron. J. Mater. Sci. 49 (2014) 2477-2482

Zhang L., Šob M., Wu Z., Zhang Y., Lu G.: Characterization of iron ferromagnetism by the local atomic volume: from three-dimensional structures to isolated atoms. J. Phys.: Condens. Matter 26 (2014) 086002

Lejček P., Zheng L., Hofmann S., Šob M.: Applied Thermodynamics: Grain Boundary Segregation. Entropy 16 (2014) 1462-1483


Hemzalová P., Friák M., Šob M., Ma D., Udyansky A., Raabe D., Neugebauer J.: Ab initio study of thermodynamic, electronic, magnetic, structural, and elastic properties of Ni4N allotropes. Phys. Rev. B 88 (2013) 174103

Černý M., Šesták P., Pokluda J., Šob M.: Shear instabilities in perfect bcc crystals during simulated tensile tests. Phys. Rev. B 87 (2013) 014117

Lejček P., Šob M., Paidar V., Vítek V.: Why calculated energies of grain boundary segregation are unreliable when segregant solubility is low. Scr. Mater. 68 (2013) 547-550


Káňa T., Šob M.: Mechanical and magnetic properties of Mn-Pt compounds and nanocomposites. Phys. Rev. B 85 (2012) 214438