TY - JOUR

T1 - Fracture of severely plastically deformed Ta and Nb

AU - Hohenwarter, Anton

AU - Wurster, Stefan

AU - Völker, Bernhard

PY - 2017/4/1

Y1 - 2017/4/1

N2 - A comparative study focusing on the fracture characteristics of severely plastically deformed (SPD) Nb and Ta is presented. Since many SPD-processes lead to typically elongated microstructures, orientation dependent fracture toughness measurements with three different crack orientations were performed. Among the various testing orientations, two exhibit a considerably high fracture toughness in both materials. The high fracture resistance in these orientations will be discussed on the basis of the significance of crack deflection and delamination processes. In both materials the lowest fracture toughness was found in the third testing orientation parallel to the grain elongation. However, between Nb and Ta the fracture toughness differs in this orientation by a factor of three, rendering Nb even parallel to the grain alignment to a quite fracture resistant material.

AB - A comparative study focusing on the fracture characteristics of severely plastically deformed (SPD) Nb and Ta is presented. Since many SPD-processes lead to typically elongated microstructures, orientation dependent fracture toughness measurements with three different crack orientations were performed. Among the various testing orientations, two exhibit a considerably high fracture toughness in both materials. The high fracture resistance in these orientations will be discussed on the basis of the significance of crack deflection and delamination processes. In both materials the lowest fracture toughness was found in the third testing orientation parallel to the grain elongation. However, between Nb and Ta the fracture toughness differs in this orientation by a factor of three, rendering Nb even parallel to the grain alignment to a quite fracture resistant material.

KW - Fracture toughness

KW - High pressure torsion

KW - Nanocrystalline

KW - Niobium

KW - Severe plastic deformation

KW - Tantalum

KW - Ultrafine-grained

UR - http://www.scopus.com/inward/record.url?scp=85010735707&partnerID=8YFLogxK

U2 - 10.1016/j.ijrmhm.2016.12.009

DO - 10.1016/j.ijrmhm.2016.12.009

M3 - Article

AN - SCOPUS:85010735707

VL - 64.2017

SP - 143

EP - 150

JO - International Journal of Refractory Metals and Hard Materials

JF - International Journal of Refractory Metals and Hard Materials

SN - 0263-4368

IS - April

ER -