A Hexagonal Grid Sampling Scheme for Improving X-ray Diffraction Retained Austenite Measurements of Sheet Steels

Published

February 1, 2023

Author(s)

Michael Cox, Adam Creuziger, Kip Findley

Abstract

Advanced High Strength Steels make use of retained austenite to improve mechanical properties. The benefits of the austenitic phase are directly tied to the phase fraction present in a material. However, phase characterization of retained austenite is complicated by the often metastable nature of the phase and the presence of crystallographic texture in many steel products. Diffraction based measurements of retained austenite in particular exhibit large texture bias errors in the measurement of sheet steels. The wide availability of low-energy X-ray diffraction equipment, however, makes the method attractive for relatively rapid characterization of materials. Reducing texture bias error for X-ray measurements of retained austenite therefore may benefit both industry and research. A method of reducing the texture bias error using a hexagonal grid sampling scheme has been investigated via simulations and validated experimentally. The sampling scheme consists of measuring the sample at multiple diffraction vectors of roughly even spacing on the pole figure. Simulation and experimental results agreed closely, particularly for the commonly performed normal direction measurement. The 30° hex scheme simulations and experimental measurement exhibited greatly reduced texture bias error.

Citation

Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science

Volume

56

Pub Type

Journals

Download Paper

https://doi.org/10.1007/s11661-022-06931-8

Local Download

Keywords

X-ray Diffraction, Sampling Scheme, Crystallographic Texture, Retained Austenite, Characterization, Phase Measurement

Citation

Cox, M. , Creuziger, A. and Findley, K. (2023), A Hexagonal Grid Sampling Scheme for Improving X-ray Diffraction Retained Austenite Measurements of Sheet Steels, Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, [online], https://doi.org/10.1007/s11661-022-06931-8, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=934933 (Accessed April 23, 2024)