アカツ　タカシ   赤津　隆    所属   片柳研究所 研究者    職種   教授
言語種別	英語
発行・発表の年月	2024/11
形態種別	学術論文
査読	査読あり
標題	Weight functions for point-sharp nanoindentation to evaluate the mechanical properties of a film/coating on a substrate
執筆形態	共著
掲載誌名	Results in Engineering
掲載区分	国外
出版社・発行元	Elsevier
巻・号・頁	24,pp.103447
総ページ数	14
担当区分	筆頭著者,責任著者
著者・共著者	Hayato Inuzuka, Yutaka Shinoda, and Fumihiro Wakai
概要	The mechanical properties evaluation of a film/coating (F/C) on a substrate is one of the required targets of nanoindentation. In terms of nanoindentation on F/C, the relationship between the indentation load, P, and penetration depth, h, so called P-h curve, changes transitionally as the maximum value of h, hm, increases even using a point-sharp indenter. This study aims to develop two weight functions which describe the transitional changes as a function of hc/t, where hc is the contact depth and t is the F/C thickness, focusing on two important indentation parameters for evaluating the elastic modulus and yield stress of F/Cs: the indentation elastic parameter ke (≡P/h^2 for perfectly elastic solids) and relative residual depth  (≡h_r/h_m with hr: residual depth). The weight functions were derived from simulated P-h curves using the finite element method, where the mechanical properties of both the F/C and the substrate were systematically varied. The elastic modulus of F/C was evaluated using the ke-value of F/C obtained by extrapolating ke-weight function to hc/t = 0. The yield stress of the F/C was evaluated using the elastic-plastic index with the elastic modulus and guzai-value of the substrate obtained by extrapolating guzai-weight function hc/t = 0. hc required to obtain the weight functions was determined as a converged value of iterative calculation proposed to evaluate the elastic modulus and yield stresses of F/Cs.
researchmap用URL	https://doi.org/10.1016/j.rineng.2024.103447
論文（査読付）ファイル	DOWNLOAD