Studium teplotní stability ultrajemnozrnné mědi pomocí metody EBSD

Study of Thermal stability of Ultrafine-grained Copper by means of Electron Back Scattering Diffraction

článek v časopise - ostatní, Jost

en

Thermal stability of ultrafine-grained (UFG) structure of 99.9% pure copper produced by eight equal channel angular pressing (ECAP) passes was studied. The annealing experiments were conducted at 180degC in a tube furnace under argon as a covering gas. The dwell times were in the range of 10 min to 120 min. The electron backscattering diffraction (EBSD) analyses were performed before and after annealing at exactly the same area in order to quantify the degree of decomposition of the UFG structure. Definition of grain boundaries was based on the misorientation angle of 1. More advanced analysis of the EBSD results based on a kernel average misorientation (KAM) parameter was performed. Inverse pole figure maps with included grain networks did not reveal any substantial changes of UFG microstructure due to annealing. Some shift in the KAM modus in comparison with the initial state was observed but its magnitude was found negligible. Also changes in texture were found to be minor. On the other hand the microhardness increases with increasing time of annealing.

V clanku byla studována teplotní stabilita UFG Cu připravené metodou ECAP. ŽihaciÍ experiment byl provaden pri teplote 180degC v rozsahu vydrzÍ od 10 do 120 minut. Mikrostrukturní změny byly zjišťovány pomocí EBSD techniky. Výsledky ukázaly, že v důsledku teplotní expozice (při dané úrovni teploty) nedošlo k výrazným mikrostrukturním změnám.

Thermal stability of ultrafine-grained (UFG) structure of 99.9% pure copper produced by eight equal channel angular pressing (ECAP) passes was studied. The annealing experiments were conducted at 180degC in a tube furnace under argon as a covering gas. The dwell times were in the range of 10 min to 120 min. The electron backscattering diffraction (EBSD) analyses were performed before and after annealing at exactly the same area in order to quantify the degree of decomposition of the UFG structure. Definition of grain boundaries was based on the misorientation angle of 1. More advanced analysis of the EBSD results based on a kernel average misorientation (KAM) parameter was performed. Inverse pole figure maps with included grain networks did not reveal any substantial changes of UFG microstructure due to annealing. Some shift in the KAM modus in comparison with the initial state was observed but its magnitude was found negligible. Also changes in texture were found to be minor. On the other hand the microhardness increases with increasing time of annealing.

ultrajemnozrnná měď, teplotní stabililta, EBSD, velikost zrna, textura

ultra-fine grained copper, thermal stability of microstructure, EBSD, grain size, texture

2010

25.01.2010

The Japan Institute of Metals

Japonsko

1345-9678

MATERIALS TRANSACTIONS

51

2

209–213

5