On the Elementary Wear Mechanisms of UD-GFRP Composites Using Single Indenter Scratch Test

Abrasive wear limits the lifetime of key components and wear parts used in various applications. Damage is caused by indentation of harder particles into the wearing materials and subsequent relative motion resulting in ploughing, cutting, and fracture phenomena. The wear mechanisms depend mainly on the applied materials, loading conditions, and abrasives present in the tribosystem, hence material choice is often a difficult task and requires careful evaluation. For this, a variety of laboratory abrasion tests are available of which the scratch test is discussed in this work as the most fundamental abrasive interaction. For further insight into the acting wear mechanisms and microstructural effects, large-scale molecular dynamics simulations were carried out as well as meso-/macroscopic scratch simulations with the mesh-free Material Point Method. The prediction of abrasive wear is of high relevance for industrial applications. Up to now, no general one-to-one match between field application and lab system is known. Here, a simulation-based transfer of experimentally determined wear rates via a lab-2-field approach enables the prediction of wear rates in real applications.

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Cavitation Erosion and Sliding Wear Mechanisms of AlTiN and TiAlN Films Deposited on Stainless Steel Substrate

Coatings ◽

10.3390/coatings9050340 ◽

2019 ◽

Vol 9 (5) ◽

pp. 340 ◽

Cited By ~ 13

Author(s):

Mirosław Szala ◽

Mariusz Walczak ◽

Kamil Pasierbiewicz ◽

Mariusz Kamiński

Keyword(s):

Stainless Steel ◽

Wear Mechanisms ◽

Sliding Wear ◽

Cavitation Erosion ◽

Chemical Elements ◽

Steel Substrate ◽

Reference Sample ◽

Scratch Test ◽

Film Rupture ◽

Columnar Grain

The resistance to cavitation erosion and sliding wear of stainless steel grade AISI 304 can be improved by using physical vapor deposited (PVD) coatings. The aim of this study was to investigate the cavitation erosion and sliding wear mechanisms of magnetron-sputtered AlTiN and TiAlN films deposited with different contents of chemical elements onto a stainless steel SS304 substrate. The surface morphology and structure of samples were examined by optical profilometry, light optical microscopy (LOM) and scanning electron microscopy (SEM-EDS). Mechanical properties (hardness, elastic modulus) were tested using a nanoindentation tester. Adhesion of the deposited coatings was determined by the scratch test and Rockwell adhesion tests. Cavitation erosion tests were performed according to ASTM G32 (vibratory apparatus) in compliance with the stationary specimen procedure. Sliding wear tests were conducted with the use of a nano-tribo tester, i.e., ball-on-disc apparatus. Results demonstrate that the cavitation erosion mechanism of the TiAlN and AlTiN coatings rely on embrittlement, which can be attributed to fatigue processes causing film rupture and internal decohesion in flake spallation, and thus leading to coating detachment and substrate exposition. At moderate loads, the sliding wear of thin films takes the form of grooving, micro-scratching, micro-ploughing and smearing of the columnar grain top hills. Compared to the SS reference sample, the PVD films exhibit superior resistance to sliding wear and cavitation erosion.

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A micromechanical scratch model to investigate wear mechanisms in UD-GFRP composites

Mechanics & Industry ◽

10.1051/meca/2018011 ◽

2018 ◽

Vol 19 (3) ◽

pp. 305 ◽

Cited By ~ 1

Author(s):

Slah Mzali ◽

Fatma Elwasli ◽

Ali Mkaddem ◽

Salah Mezlini

Keyword(s):

Glass Fiber ◽

Wear Mechanisms ◽

Material Removal ◽

Normal Load ◽

Scratch Test ◽

Attack Angle ◽

Material Behavior ◽

Fe Model ◽

Cohesive Elements ◽

Composite Damage

This study suggests a micromechanical approach to scrutinize the glass fiber reinforced polyester (GFRP) composite tribological behavior. A single indenter scratch test (SST) using spherical tip conical indenter was adopted. The 3D finite element (FE) model was developed into ABAQUS/Explicit commercial code. Both material behavior and damage of polyester matrix and glass fiber was modeled using the Johnson Cook behavior law. Nevertheless, the fiber/matrix interface behavior is described using the cohesive zone approach via the cohesive elements. The elementary wear mechanisms owing to the SST were appraised at different attack angle and normal load by the mean of scanning electron microscope (SEM). In this work, the material removal map was built to emphasize the correlation between the tribological parameters, particularly the attack angle and the normal load, and the material removal process. The numerical results emphasized the significant effects of the attack angle and the penetration depth on the transition of the wear mechanisms from ploughing to composite damage. The experimental wear mechanisms and the predicted elementary wear mechanisms seem to be in a good agreement.

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Cavitation Erosion and Wear Mechanisms of AlTiN and TiAlN Films Deposited on Stainless Steel Substrate

10.20944/preprints201904.0228.v1 ◽

2019 ◽

Author(s):

Mirosław Szala ◽

Mariusz Walczak ◽

Kamil Pasierbiewicz ◽

Mariusz Kamiński

Keyword(s):

Stainless Steel ◽

Elastic Modulus ◽

Wear Mechanisms ◽

Sliding Wear ◽

Cavitation Erosion ◽

Stainless Steel Substrate ◽

Steel Substrate ◽

Scratch Test ◽

Optical Microscope ◽

Material Transfer

Stainless steel grade AISI 304 is one of the most widespread modern structural material, alas its sliding wear and cavitation wear resistance are limited. Thus, AlTiN and TiAlN coatings can be deposited for increasing the resistance to wear of stainless steel components. The aim of the work was to investigate the cavitation erosion and sliding wear mechanisms of magnetron sputtered AlTiN and TiAlN coatings deposited on SS304 stainless steel. Films surface morphology and structure were examined using a profilometer, light optical microscope (LOM) and scanning electron microscope (SEM). The mechanical properties (hardness, elastic modulus) were tested by nanoindentation tester. The adhesion of deposited coatings was determined by means of the scratch test and Rockwell test. Cavitation erosion tests were performed according to ASTM G32 (vibratory apparatus) with stationary specimen procedure. Sliding wear tests were conducted using a nano-tribo testes i.e. ball-on-disc apparatus. Wear mechanisms are strongly contingent upon the structure and morphology of the tested materials. In relation to stainless steel substrate, the PVD films present a superior resistance to sliding wear and cavitation erosion. Higher resistance was noticed for AlTiN than for TiAlN film, mainly due to its superior hardness and elastic modulus. Cavitation erosion mechanism of both, AlTiN and AlTiN coatings is prone to embrittlement, imputable to fatigue processes that result in coating rupture and spallation that consist in coating fragmentation, formation of pits and finally detachment from the substrate. Additionally, films nanoindentation results measured before and after cavitation testing indicate changes in coatings structure, that acknowledged wear mechanism that starts with coating internal delamination in flake spallation mode. In contrary to PVD coatings, steel substrate is characterized by developed cavitation erosion wear with roughened surface and plastically deformed, semi-brittle, eroded surface. Sliding wear of thin films is based on micro-ploughing mechanism. For stainless steel adhesive sliding wear mode and plastic deformation with smearing, material transfer and grooving were observed. It was confirmed that various fluid machinery components made from austenitic stainless steel that undergo cavitation erosion, can be prevented by deposition of AlTiN and TiAlN films.

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The Correlation of Adhesion Strength with Barrier Structure in Cu Metallization

MRS Proceedings ◽

10.1557/proc-766-e.3.5 ◽

2003 ◽

Vol 766 ◽

Author(s):

A. Sekiguchi ◽

J. Koike ◽

K. Ueoka ◽

J. Ye ◽

H. Okamura ◽

...

Keyword(s):

Thin Films ◽

Adhesion Strength ◽

Nitrogen Concentration ◽

Scratch Test ◽

Barrier Structure ◽

Barrier Layers ◽

Cu Metallization ◽

Microstructure Observation ◽

Sputter Deposited ◽

Sulfur Containing

AbstractAdhesion strength in sputter-deposited Cu thin films on various types of barrier layers was investigated by scratch test. The barrier layers were Ta1-xNx with varied nitrogen concentration of 0, 0.2, 0.3, and 0.5. Microstructure observation by TEM indicated that each layer consists of mixed phases of β;-Ta, bcc-TaN0.1, hexagonal-TaN, and fcc-TaN, depending on the nitrogen concentration. A sulfur- containing amorphous phase was also present discontinuously at the Cu/barrier interfaces in all samples. Scratch test showed that delamination occurred at the Cu/barrier interface and that the overall adhesion strength increased with increasing the nitrogen concentration. A good correlation was found between the measured adhesion strength and the composing phases in the barrier layer.

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