Institute of Physics of Materials AS CR, v. v. i. > Projects > The role of stress state and vacancy supersaturation at the formation of binary hollow nanoparticles

The role of stress state and vacancy supersaturation at the formation of binary hollow nanoparticles

InvestigatorRNDr. Jiří Svoboda, CSc., DSc.
Number of ProjectP108-10-1781
AgencyGrantová agentura České republiky
Duration2009-12-31 - 2012-12-30

Anotace
The formation of hollow nanospheres by means of gas-solid reaction of metallic nanospheres with an external gas atmosphere is a well known problem. From the experimental studies it is evident that the formation of a hollow nanosphere of stoichiomentric phase MpXq must be preceded by the formation of a sufficiently thick MpXq nanoshell on the metallic core of phase M. The developed theoretical models assume that a significant supersaturation of vacancies and/or a very high hydrostatic stress are built up in the M core due to Kirkendall effect, which leads to the nucleation of a hollow by vacancy condensation. The developed models indicate that the building of the very high hydrostatic stress in the M core is decisive for the hollow nucleation.


2013

Appel F., Herrmann D., Fischer F., Svoboda J., Kozeschnik E.: Role of Vacancies in Work Hardening and Fatigue of TiAl Alloys. Int. J. Plast. 42 (2013) 83-100

Hackl K., Fischer F., Klevakina K., Renner J., Svoboda J.: A Variational Approach to Grooving and Wetting. Acta Mater. 61 (2013) 1581-1591



2012

Svoboda J., Fischer F., McDowell D.: Derivation of the phase field equations from the thermodynamic extremal principle. Acta Mater. 60 (2012) 396-406

Fischer F., Svoboda J., Hackl K.: Modelling the Kinetics of a Triple Junction. Acta Mater. 60 (2012) 4704-4711



2011

Fischer F., Svoboda J., Appel F., Kozeschnik E.: Modelling of Excess Vacancy Annihilation at Different Types of Sinks. Acta Mater. 59 (2011) 3463-3472

Svoboda J., Fischer F.: Stress Development During Reaction of Metallic Nanospheres with Gas. Acta Mater. 59 (2011) 61-67

Fischer F., Svoboda J.: Modelling of Reaction of Metallic Nanospheres with Gas. Solid State Phenom. 172-174 (2011) 1028-1037