Multi-layer and composite structures for advanced coatings

Zheng, Lanshi; Ramalingam, S.

doi:10.1016/0257-8972(95)02618-5

Cited by 32 publications

(7 citation statements)

References 4 publications

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“…By matching the mechanical properties of the initial stages of the coating to that of the substrate, compatibility is enhanced and interfacial stresses are reduced. This concept has been discussed by Ramalingam and Zheng, , who studied high hardness coatings on metals, and Jen et al, who studied barrier films on Teflon. They both discuss the use of interlayers to achieve a mechanical match between substrate and coating.…”

Section: Discussionmentioning

confidence: 99%

Direct Imaging of Mechanical and Chemical Gradients Across the Thickness of Graded Organosilicone Microwave PECVD Coatings

Hall

Murphy

Griesser

2014

ACS Appl. Mater. Interfaces

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The characterization of variations in the chemical composition and ensuing mechanical properties across the thickness of coatings with continuously varying compositions through their thickness (graded coatings) presents considerable challenges for current analytical techniques in materials science. We report here the direct imaging of nanomechanical and chemical gradients across cross-sections of an organosilicone coating fabricated via microwave plasma enhanced chemical vapor deposition (PECVD). Cross-sectional nanoindentation was used to determine the mechanical properties of uniform and graded organosilicone coatings. Both hardness and modulus across the coatings were directly measured. Additionally, "modulus mapping" on cross-sections was used to map the complex modulus. For the graded coating, it was found that variations in the complex modulus was predominantly due to varying storage modulus. It was observed that at the interface with the substrate there was a low storage modulus, which linearly increased to a relatively high storage modulus at the surface. It is proposed that the increase in stiffness, from the substrate interface to the outer surface, is due to the increasing content of a cross-linked O-Si-O network. This mechanical gradient has been linked to a change in the Si:O ratio via direct compositional mapping using ToF-SIMS. Direct mapping of the mechanical and compositional gradients across these protective coatings provides insight into the changes in properties with depth and supports optimization of the critical mechanical performance of PECVD graded coatings.

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Section: Discussionmentioning

confidence: 99%

Direct Imaging of Mechanical and Chemical Gradients Across the Thickness of Graded Organosilicone Microwave PECVD Coatings

Hall

Murphy

Griesser

2014

ACS Appl. Mater. Interfaces

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“…The detrimental effects of low substrate hardness were also seen with investigation of erosion resistance on TiN coatings on tool steel [22]. Ramalingam and Zheng [80,81] noted that matching the elastic moduli of coatings and substrates will reduce tensile flexural stresses and therefore reduce film cracking alongside thicker coatings further reducing this stress . Therefore, it can be concluded coating fatigue resistance is first controlled by the substrate's ability to support the coating structure and substrate properties must be considered for a well performing composite [82].…”

Section: On the Significance Of Substrate Hardnessmentioning

confidence: 97%

Probing fatigue resistance in multi-layer DLC coatings by micro- and nano-impact: Correlation to erosion tests

McMaster

Liskiewicz

Neville

et al. 2020

Surface and Coatings Technology

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DLC coatings have seen recent use as protective coatings for flow control devices in the oil and gas industries. Improving fatigue resistance for multi-layered DLC coatings on hardened steel is key for improving their performance in this harsh environment of highly loads repetitive contact. This has been studied directly by micro-scale repetitive impact tests at significantly higher strain rate and energy than in the nano-impact test, enabling the study of coating fatigue with spherical indenters and dry erosion testing. Nano-impact has also been used to assess the initial fatigue behaviour of the coatings. Good correlation between microimpact results and erosion results was found. Hard multi-layered a-C:H and Si-a-C:H coatings were found to be significantly less durable under fatigue loading than a-C:H:W. The influence of the coating mechanical properties and structure on these differences is discussed.The results of this study provide further strong evidence that in highly loaded mechanical contact applications requiring a combination of load support and resistance to impact fatigue, the optimum lifetime of coated components may be achieved by designing the coating system to combine these properties rather than by solely aiming to maximise coating hardness as this may be accompanied by brittle fracture and higher wear.

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“…They comprise layered composites as well as multilayered coats. The contact problems for multilayered solids have considered in papers [9][10][11][12][13][14][15][16][17]. In the above-cited investigations authors derived calculations for the body composed of small number of layers.…”

Section: Introductionmentioning

confidence: 99%

On axisymmetrical contact problem of pressure of a rigid sphere into a periodically two-layered semi-space

Kulchytsky-Zhyhailo

Kołodziejczyk

2007

International Journal of Mechanical Sciences

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Multi-layer and composite structures for advanced coatings

Cited by 32 publications

References 4 publications

Direct Imaging of Mechanical and Chemical Gradients Across the Thickness of Graded Organosilicone Microwave PECVD Coatings

Direct Imaging of Mechanical and Chemical Gradients Across the Thickness of Graded Organosilicone Microwave PECVD Coatings

Probing fatigue resistance in multi-layer DLC coatings by micro- and nano-impact: Correlation to erosion tests

On axisymmetrical contact problem of pressure of a rigid sphere into a periodically two-layered semi-space

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