614 Critical Indentation Depth to Determine Mechanical Properties of Thin Films

2006 ◽  
Vol 2006.19 (0) ◽  
pp. 291-292
Author(s):  
Norimasa Chiba ◽  
Kensuke Kanbe ◽  
Constantin Razvan Anghel ◽  
Nagahisa Ogasawara ◽  
Xi Chen
2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Evan Raeker ◽  
Max Powers ◽  
Amit Misra

Abstract The immiscible alloy Cu–Ta has the potential for enhanced mechanical performance in applications as a functional coating. To establish baseline mechanical properties, four Cu–Ta films were co-sputtered at the temperatures 23, 400, 600, and 800 °C and tested with nanoindentation at strain rates 5 $$\times $$ × 10−3 s−1 to 10 s−1. Each film had a unique microstructure morphology. The hardness and elastic modulus of the four films were insensitive to strain rate changes. Instead, the measured properties were spatially dependent, particularly in the 600 and 800 °C films. In those two films, there is a bimodal deformation behavior due to Cu-agglomeration under protruding grains and planar Ta-rich regions. Increasing the indentation depth revealed shear band suppression which is related to a homogenous distribution of flow stresses for all four microstructure morphologies. Finally, the Cu–Ta hardness appeared to follow a rule-of-mixtures when compared to extrapolated data of Cu and Ta monolithic films.


Author(s):  
Lorenzo Calabri ◽  
Sara Mantovani ◽  
Leonardo Rettighieri ◽  
Sergio Valeri

2006 ◽  
Vol 514-516 ◽  
pp. 1472-1476
Author(s):  
Jorge M. Antunes ◽  
Nataliya A. Sakharova ◽  
José Valdemar Fernandes ◽  
Luís Filipe Menezes

Depth sensing indentation equipment allows the mechanical properties of thin films to be easily determined, particularly the hardness and Young’s modulus. In order to minimize the influence of the substrate on the measured properties, the indentation depth must be limited to a small fraction of the film’s thickness. However, for very thin films, the determination of the contribution of the substrate and the film to the measured mechanical properties becomes a hard task, because both deform plastically. The numerical simulation of ultramicrohardness tests can be a helpful tool towards better understanding of the influence of the parameters involved in the mechanical characterization of thin films. For this purpose, a three-dimensional numerical simulation home code, HAFILM, was used to simulate ultramicrohardness tests on coated substrates. Materials with different Young’s modulus film/substrate ratios were tested. Analyses of strain and stress distributions for several indentation depth values were performed, in order to clarify the composite behaviour.


2011 ◽  
Vol 99 (2) ◽  
pp. 239-244 ◽  
Author(s):  
T.T.H. Pham ◽  
E. Le Bourhis ◽  
P. Goudeau ◽  
P. Guérin

2009 ◽  
Vol 113 (2) ◽  
pp. 976-983 ◽  
Author(s):  
Wonbong Jang ◽  
Jongchul Seo ◽  
Choonkeun Lee ◽  
Sang-Hyon Paek ◽  
Haksoo Han

Author(s):  
Pei Bai ◽  
Mingchao Ma ◽  
Li Sui ◽  
Yunlong Guo

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1566
Author(s):  
Oliver J. Pemble ◽  
Maria Bardosova ◽  
Ian M. Povey ◽  
Martyn E. Pemble

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.


2021 ◽  
pp. 109844
Author(s):  
Zaoli Zhang ◽  
Arsham Ghasemi ◽  
Nikola Koutná ◽  
Zhen Xu ◽  
Thomas Grünstäudl ◽  
...  

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