TY - JOUR

T1 - Deformation behavior of aluminum pillars produced by Xe and Ga focused ion beams: Insights from strain rate jump tests

AU - Xiao, Y

AU - Maier-Kiener, Verena

AU - Michler, Johann

AU - Spolenak, R.

AU - Wheeler, Jeffrey M.

PY - 2019/6/7

Y1 - 2019/6/7

N2 - Micro-compression testing of focused ion beam fabricated pillars is a popular technique for mechanical characterization at small scales. However, there are concerns associated with these ion-prepared samples, including irradiation damage from Ga ions and Ga segregation at grain boundaries resulting in liquid metal embrittlement. In this work, this is investigated using strain rate jump nanoindentation and micro-compression of single crystalline and ultrafine-grained aluminum with different grain boundary conditions. The extracted strain rate sensitivity and activation volume are used to study the effects of Ga and Xe ion species from fabrication and testing methods on deformation behavior of aluminum samples. Results show that the measured strain-rate sensitivity of non-equilibrium, ultrafine-grained aluminum is significantly affected by the dosage of Ga. Activation volumes suggest that the dominant deformation mechanism remains consistent despite Ga at the boundaries. Atom probe tomography reveals that Ga was observed to segregate to aluminum grain boundaries up to 2.2 at.% in the FIB prepared sample.

AB - Micro-compression testing of focused ion beam fabricated pillars is a popular technique for mechanical characterization at small scales. However, there are concerns associated with these ion-prepared samples, including irradiation damage from Ga ions and Ga segregation at grain boundaries resulting in liquid metal embrittlement. In this work, this is investigated using strain rate jump nanoindentation and micro-compression of single crystalline and ultrafine-grained aluminum with different grain boundary conditions. The extracted strain rate sensitivity and activation volume are used to study the effects of Ga and Xe ion species from fabrication and testing methods on deformation behavior of aluminum samples. Results show that the measured strain-rate sensitivity of non-equilibrium, ultrafine-grained aluminum is significantly affected by the dosage of Ga. Activation volumes suggest that the dominant deformation mechanism remains consistent despite Ga at the boundaries. Atom probe tomography reveals that Ga was observed to segregate to aluminum grain boundaries up to 2.2 at.% in the FIB prepared sample.

UR - http://www.scopus.com/inward/record.url?scp=85067361239&partnerID=8YFLogxK

U2 - 10.1016/j.matdes.2019.107914

DO - 10.1016/j.matdes.2019.107914

M3 - Article

VL - 181.2019

JO - Materials and Design

JF - Materials and Design

SN - 0264-1275

IS - November

M1 - 107914

ER -