High-speed nanoindentation mapping of a near-alpha titanium alloy made by additive manufacturing

• Published in: Journal of materials research 2021-06, Vol.36 (11), p.2223-2234
• Main Authors: Liu, Zhiying, Zhang, Jiahui, He, Bei, Zou, Yu
• Format: Article
• Language: English
• Subjects: Algorithms; Alloying additive; Applied and Technical Physics; Beta phase; Biomaterials; Chemistry and Materials Science; Cluster analysis; Clustering; Electron backscatter diffraction; Electron probe microanalysis; Hardness; Heat treatment; High speed; Inorganic Chemistry; Manufacturing; Mapping; Materials Engineering; Materials research; Materials Science; Microstructure; Modulus of elasticity; Molybdenum; Nanoindentation; Nanotechnology; Titanium base alloys; Vector quantization
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-021-00204-7

Titanium alloys are widely used in additive manufacturing, but their complex microstructures and related micromechanical properties have not been fully explored. Here, we employ high-speed nanoindentation mapping, electron probe microanalysis, and electron backscatter diffraction to characterize as-deposited and heat-treated Ti–6Al–2Zr–Mo–V alloys. Our results show the correlations between mechanical contrasts (hardness and elastic modulus ) and phase contrasts (α and β). The hardness and elastic modulus of the α and β phases are increased due to the element redistribution after annealing (Al diffuses from β to α; Mo and V diffuse from α to β). We use a K-means clustering algorithm to analyze the nanoindentation dataset and correlate the mechanical property maps to the distribution of α and β phases. Our study employs the emerging high-speed nanoindentation mapping to give a better understanding of the microstructure–mechanical property relationship of additive manufactured multiphase alloys across length scales. Graphic abstract