The Effect of Heat Treatment on the Microstructure and Mechanical Properties of 2D Nanostructured Au/NiFe System

Nanostructured NiFe film was obtained on silicon with a thin gold sublayer via pulsed electrodeposition and annealed at a temperature from 100 to 400 °C in order to study the effect of heat treatment on the surface microstructure and mechanical properties. High-resolution atomic force microscopy made it possible to trace stepwise evolving microstructure under the influence of heat treatment. It was found that NiFe film grains undergo coalescence twice—at ~100 and ~300 °C—in the process of a gradual increase in grain size. The mechanical properties of the Au/NiFe nanostructured system have been investigated by nanoindentation at two various indentation depths, 10 and 50 nm. The results showed the opposite effect of heat treatment on the mechanical properties in the near-surface layer and in the material volume. Surface homogenization in combination with oxidation activation leads to abnormal strengthening and hardening-up of the near-surface layer. At the same time, a nonlinear decrease in hardness and Young’s modulus with increasing temperature of heat treatment characterizes the internal volume of nanostructured NiFe. An explanation of this phenomenon was found in the complex effect of changing the ratio of grain volume/grain boundaries and increasing the concentration of thermally activated diffuse gold atoms from the sublayer to the NiFe film.

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Evolution of Microstructure and Mechanical Properties of Nanostructured NiFe Films under Influence of Heat Treatment

Science & Technique ◽

10.21122/2227-1031-2021-20-2-109-120 ◽

2021 ◽

Vol 20 (2) ◽

pp. 109-120

Author(s):

V. M. Fedosyuk

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Grain Size ◽

Surface Layer ◽

Young’S Modulus ◽

Heat Treatment Temperature ◽

Young's Modulus ◽

Treatment Temperature ◽

Microstructure And Mechanical Properties ◽

Internal Volume

. Nanostructured NiFe films were synthesized by pulsed electrolytic deposition on silicon with a gold sublayer, after which they have been subjected to to temperature treatment at 373-673 K in order to study the effect of heat treatment on the microstructure and mechanical properties of the objects under study. High-resolution atomic force microscopy has made it possible to trace the stages of microstructure evolution under the influence of heat treatment, including the process of nonlinear increase in grain growth and two-stage agglomeration. It is shown that with an increase in heat treatment temperature to 673 K, the grain size increases from 68 to 580 nm in comparison with the initial sample, undergoing agglomeration processes at temperatures of 100 and 300 °C. The mechanical properties of nanostructured NiFe films have been studied by the nanoindentation method. The dependences of the hardness of Young’s modulus and the values of the resistance to elastoplastic deformation on depth have been obtained and analyzed in the paper. This approach has permitted to reveal differences in the behavior of the mechanical properties of the surface layer and the internal volume of the film under the action of different heat treatment temperatures, as well as to demonstrate the opposite reaction of different material layers to an increase in temperature. As a result of a thorough analysis of the deformation curves of nanoindentation, it has been found that the homogenization of the surface in combination with the activation of oxidation processes leads to the strengthening of near-surface layer of NiFe films. At the same time, the internal volume of the material is characterized by a nonlinear decrease in hardness and Young’s modulus with an increase in the heat treatment temperature. The explanation for this phenomenon has been found in the complex effect of a decrease in the number of grain boundaries (due to an increase in the average grain size with increasing temperature) and an increase in the concentration of gold atoms diffusing from the sublayer more actively with an increase in the processing temperature of NiFe films.

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Heat Treatment Processes of A2024 Rheoforging Alloy and Morphology Investigation by Nanoindentation and Atomic Force Microscopy

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.141-143.385 ◽

2008 ◽

Vol 141-143 ◽

pp. 385-390 ◽

Cited By ~ 1

Author(s):

D.S. Kim ◽

C.G. Kang ◽

S.M. Lee

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Atomic Force Microscopy ◽

Aluminum Alloy ◽

Phase Region ◽

Force Microscopy ◽

T6 Heat Treatment ◽

Treatment Processes ◽

Atomic Force ◽

Wrought Aluminum

This study demonstrated nanoindentation techniques of investigating the effects of size and feature in a microstructure on the mechanical properties of rheology-forged aluminum alloy. Mechanical properties and tribological characteristics of rheology-forged Al2024 wrought aluminum alloy in terms of T6 heat treatment were investigated by varying the aging time by nanoindentation and nanoscratch techniques. By nanoindentation/nanoscratch tests and atomic force microscopy, it was demonstrated that the 4 hour aged material exhibites the highest hardness because of the intermediate precipitate phase θ″, which was precipitated by T6 heat treatment at 495°C. Moreover, the friction coefficients in the precipitates in the eutectic phase region were lower than those in the primary α phase region.

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Investigation of Near-Surface Mechanical Properties of Materials Using Atomic Force Microscopy

Experimental Mechanics ◽

10.1007/s11340-013-9719-4 ◽

2013 ◽

Vol 54 (1) ◽

pp. 11-24 ◽

Cited By ~ 4

Author(s):

D. Su ◽

X. Li

Keyword(s):

Mechanical Properties ◽

Atomic Force Microscopy ◽

Near Surface ◽

Force Microscopy ◽

Atomic Force ◽

Mechanical Properties Of Materials ◽

Properties Of Materials

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Mechanical Properties of TiO2 nanotubes investigated by AFM and FEM

10.21203/rs.3.rs-36131/v1 ◽

2020 ◽

Author(s):

Ji Zhou ◽

Zuozhang Wang ◽

Yunhong Jiang ◽

Zhongmei Yang ◽

Qiong Tian ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Finite Element Method ◽

Elastic Modulus ◽

Tio2 Nanotubes ◽

The Finite Element Method ◽

Mechanical Behaviors ◽

Force Microscopy ◽

Atomic Force ◽

Mechanical Measurements

Abstract The mechanical measurements of nanostructures are crucial to the development and processing of novel nanodevices. Herein, TiO2 nanotubes were synthesized from an electrospun method combined with subsequent heat-treatment. The elastic modulus and fracture strength of a single TiO2 nanotube were measured by atomic force microscopy (AFM). The effect of elastic modulus and dimensional size on the mechanical behaviors of the nanotubes was simulated by the finite element method (FEM).

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