Rediscovering the intrinsic mechanical properties of bulk nanocrystalline indium arsenide

• Published in: Nanoscale Vol. 15; no. 16; pp. 7517 - 7525
• Main Authors: Li, Shuaiqi, Zhang, Jiawei, Guan, Shixue, Guo, Ruiang, He, Duanwei
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 27.04.2023
• Subjects: Bulk density; Crystal defects; First principles; Grain boundaries; Grain size; Indium arsenides; Intermetallic compounds; Mechanical properties; Molecular dynamics; Nanocrystals; Nanoindentation; Phase transitions; Single crystals; Synthesis
• ISSN: 2040-3364; 2040-3372; 2040-3372
• DOI: 10.1039/d3nr00174a

Is the inverse Hall-Petch relation in ceramic systems the same as that in metal systems? The premise to explore this subject is the synthesis of a dense bulk nanocrystalline material with clean grain boundaries. By using the reciprocating pressure-induced phase transition (RPPT) technique, compact bulk nanocrystalline indium arsenide (InAs) has been synthesized from a single crystal in a single step, while its grain size is controlled by thermal annealing. The influence of macroscopic stress or surface states on the mechanical characterization has been successfully excluded by combining first-principles calculations and experiments. Unexpectedly, nanoindentation tests show a potential inverse Hall-Petch relation in the bulk InAs with a critical grain size ( D cri ) of 35.93 nm in the experimental scope. Further molecular dynamics investigation confirms the existence of the inverse Hall-Petch relation in the bulk nanocrystalline InAs with D cri = 20.14 nm for the defective polycrystalline structure, with its D cri significantly affected by the intragranular-defect density. The experimental and theoretical conclusions comprehensively reveal the great potential of RPPT in the synthesis and characterization of compact bulk nanocrystalline materials, which provides a novel window to rediscover their intrinsic mechanical properties, for instance, the inverse Hall-Petch relation of bulk nanocrystalline InAs. The inverse Hall-Petch effect is observed in a bulk nanostructured material synthesized in one step using the reciprocating pressure-induced phase transition technique. Molecular dynamics simulation provides further evidence of its existence in InAs.