Stress, interfacial effects and mechanical properties of nanoscale multilayered coatings

Abadias, G.; Michel, A.; Tromas, C.; Jaouen, C.; Dub, S. N.

doi:10.1016/j.surfcoat.2007.05.068

Cited by 103 publications

(49 citation statements)

References 122 publications

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“…Nanoindentation experiments were performed using a MTS Nanoindenter XP with a spherical diamond indenter tip (radius R=5 The indentation procedure was performed with a MTS standard method (XP Basic) with a loading rate of 1 mN/s. For the microstructural investigation after indentation, TEM samples were prepared using the focused ion beam (FIB) technique (details are given in [18,[21][22][23]). To mark the location of the indented surface for FIB preparation, the indents selected for subsequent microstructural analysis (with relatively small maximum loads of 10 and 30 mN) were placed between two marking indents (with larger indentation depths for easier microscope).…”

Section: Methodsmentioning

confidence: 99%

TEM investigation of the microstructural evolution during nanoindentation of NiTi

Pfetzing

Wagner

Simon

et al. 2009

ESOMAT 2009 - 8th European Symposium on Martensitic Transformations

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Abstract. The continuous measurement of loads and displacements during nanoindentation of shape memory alloys allows a detailed investigation of pseudoelasticity on the nano-scale. However, the resulting load-displacement data simultaneously reflect several elastic and inelastic deformation processes (i.e., stress-induced martensitic transformation, plastic deformation). In the present study, we perform microstructural investigations in order to analyze the complex interactions between these mechanisms in a Ni-rich alloy. The microstructures below indents from experiments with different maximum indentation loads are characterized post-mortem by transmission electron microscopy. For small maximum indentation loads, load-displacement data exhibit considerable pseudoelastic recovery, whereas higher indentation loads are associated with a more pronounced residual deformation after unloading. These differences are clearly related to microstructural changes below the indenter tip: While both stressinduced martensitic transformation and dislocation slip occur in general, higher maximum loads are associated with an increase in plastic deformation. The corresponding higher dislocation densities impede the reverse transformation to austenite. Stabilized martensite can be observed directly below the surface for high indentation loads. Our results show that nanoindentation of NiTi allows a systematic analysis of the interaction of plastic deformation and stress induced transformation into martensite.

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Section: Methodsmentioning

confidence: 99%

TEM investigation of the microstructural evolution during nanoindentation of NiTi

Pfetzing

Wagner

Simon

et al. 2009

ESOMAT 2009 - 8th European Symposium on Martensitic Transformations

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“…One example highly relevant for this thesis is the study of the effect of coherency strain on the stability of the c-Al-N phase 69,70 . In many other investigations multilayer concepts have been applied in order to improve the thermal stability and the hardness over single layer coatings 69,71,72,73 . Most relevant studies for this work are Ti-Al-N/Ti-N multilayer coatings exhibiting higher hardness compared to the Ti-Al-N coating at high annealing temperatures 7,8,23 .…”

Section: Multilayer Multicomponent Alloyingmentioning

confidence: 99%

Multicomponent Alloying for Improved Hard Coatings

Forsén¹

2014

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The cover image shows an energy dispersive elemental map of a Ti-Cr-Al-N coating heated at 1100 ºC for 2 hours, Ti (red), Cr (blue) and Al (green). The domain size is around 20 nanometers.© Rikard Forsén, unless otherwise stated ISSN: 0345-7524 Printed by LiU-Tryck, Linköping, Sweden, 2014 AbstractCoatings are vital to protect and to increase the productivity of cutting tools in high speed and dry cutting applications. During the cutting operation the temperature may exceed 1000 ºC it is therefore necessary that the coatings withstand high temperatures. A lot of development and research has been carried out during the last 30 years on finding new coating material systems providing enhanced properties such as adhesion, hardness and oxidation resistance at elevated temperatures. This thesis is based on multicomponent alloying of quaternary transition metal nitride hard coatings with a main focus on Ti-CrAl-N coatings. Many different coatings and compositions have been deposited using an industrial scale cathodic arc evaporation deposition system. All deposited coatings contain Al as this element is known to increase the hardness and the oxidation resistance of nitride coatings. The deterioration of the hardness in Al-containing nitride coatings is generally attributed to the transformation of cubic Al-N into hexagonal Al-N and the consequent domain coherency relaxation. This thesis investigates these phenomena on an atomic level providing a deeper understanding of and a way to engineer improved hard nitride coatings. The essence of this thesis is that by adding a third metal to a ternary nitride material system, for example one of the most frequently used Ti-Al-N, it is possible to tune and engineer the thermal stability of the cubic structure and the coherency strain which in turn affects the hardness and the oxidation resistance. The key point is that new intermediate phases in the decomposition process are generated so that the eventual detrimental phases are suppressed and delayed. More specifically, when Cr is added to the Ti-Al-N material system the coatings exhibit an age hardening process up to 1000 ºC caused by spinodal decomposition into coherent TiCr-and AlCr-rich cubic TiCr-Al-N domains. This means that the unstable cubic Ti-Cr-Al-N phase decomposes via yet another unstable cubic Cr-Al-N phase before the detrimental hexagonal transformation of Al-N takes place. The hardness is therefore retained up to a higher temperature compared to Ti-Al-N coatings.By utilizing multicomponent alloying through addition of Ti to Cr-Al-N coatings the hardness is retained after annealing up to 1100 ºC. This is a dramatic improvement compared to Cr-Al-N coatings. Here the Ti addition promotes the competitive spinodal decomposition into TiCr-and Al-enriched domains suppressing the detrimental hexagonal Al-N formation.To investigate the effect of multicomponent alloying for other material systems with different mixing free energies and atomic sizes, Zr-containing, Zr-Cr-Al-N and Zr-Ti-Al-N, quaternary nitride coatings ...

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“…TM-nitride/metal multilayers which combine hard and soft materials (TiN/Ni 19,20 and TiN/Pt, 21 for example) have been suggested as potential candidates for protective coatings which are both hard and tough. 22 NbN/Mo 23,24 and NbN/W 24 multilayers also exhibit improved high-temperature stability compared to TM-nitride/TM-nitride multilayer systems due to immiscibility. 25 Here, as an alternative to TM-nitride/metal multilayers, we explore a different synthesis route for the growth of multilayers that combine harder and softer materials.…”

Section: Introductionmentioning

confidence: 99%

Novel hard, tough HfAlSiN multilayers, defined by alternating Si bond structure, deposited using modulated high-flux, low-energy ion irradiation of the growing film

Fager

Howe

Greczyński

et al. 2015

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

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Hf 1−x−y Al x Si y N (0 ≤ x ≤ 0.14, 0 ≤ y ≤ 0.12) single layer and multilayer films are grown on Si(001) at 250• C using ultra-high vacuum magnetically-unbalanced reactive magnetron sputtering from a single Hf 0.6 Al 0.2 Si 0.2 target in mixed 5%-N 2 /Ar atmospheres at a total pressure of 20 mTorr (2.67 Pa). The composition and nanostructure of Hf 1−x−y Al x Si y N films are controlled by varying the energy E i of the ions incident at the film growth surface while maintaining the ion-to-metal flux ratio constant at eight. Switching E i between 10 and 40 eV allows the growth of Hf 0.78 Al 0.10 Si 0.12 N/Hf 0.78 Al 0.14 Si 0.08 N multilayers with similar layer compositions, but in which the Si bonding state changes from predominantly Si-Si/Si-Hf for films grown with E i = 10 eV, to primarily Si-N with E i = 40 eV. Multilayer hardness values, which vary inversely with bilayer period Λ, range from 20 GPa with Λ = 20 nm to 27 GPa with Λ = 2 nm, while fracture toughness increases directly with Λ. Multilayers with Λ = 10 nm combine relatively high hardness, H ∼ 24 GPa, with good fracture toughness.

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Stress, interfacial effects and mechanical properties of nanoscale multilayered coatings

Cited by 103 publications

References 122 publications

TEM investigation of the microstructural evolution during nanoindentation of NiTi

TEM investigation of the microstructural evolution during nanoindentation of NiTi

Multicomponent Alloying for Improved Hard Coatings

Novel hard, tough HfAlSiN multilayers, defined by alternating Si bond structure, deposited using modulated high-flux, low-energy ion irradiation of the growing film

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