Paints and varnishes. Scratch test

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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Tribological behavior of jaspilite evaluated by micro-scratch test

10.26678/abcm.cobem2017.cob17-2398 ◽

2017 ◽

Cited By ~ 1

Author(s):

Renan Magnol ◽

Marciano Macedo ◽

Marcelo de Macêdo ◽

Cherlio Scandian

Keyword(s):

Tribological Behavior ◽

Scratch Test

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Paints and varnishes - Scratch test using a spring-loaded pen

10.3403/30421143 ◽

2021 ◽

Keyword(s):

Scratch Test

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An Assessment of Surface Treatments for Adhesion of Polyimide Thin Films

Polymers ◽

10.3390/polym13121955 ◽

2021 ◽

Vol 13 (12) ◽

pp. 1955

Author(s):

Marco Cen-Puc ◽

Andreas Schander ◽

Minerva G. Vargas Gleason ◽

Walter Lang

Keyword(s):

Flexible Electronics ◽

Oxygen Plasma ◽

Reactive Ion Etching ◽

Peel Test ◽

Scratch Test ◽

Peel Strength ◽

Surface Treatments ◽

Oxygen Plasma Treatment ◽

Polyimide Films ◽

Ion Etching

Polyimide films are currently of great interest for the development of flexible electronics and sensors. In order to ensure a proper integration with other materials and PI itself, some sort of surface modification is required. In this work, microwave oxygen plasma, reactive ion etching oxygen plasma, combination of KOH and HCl solutions, and polyethylenimine solution were used as surface treatments of PI films. Treatments were compared to find the best method to promote the adhesion between two polyimide films. The first selection of the treatment conditions for each method was based on changes in the contact angle with deionized water. Afterward, further qualitative (scratch test) and a quantitative adhesion assessment (peel test) were performed. Both scratch test and peel strength indicated that oxygen plasma treatment using reactive ion etching equipment is the most promising approach for promoting the adhesion between polyimide films.

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Silencing ZEB2 Induces Apoptosis and Reduces Viability in Glioblastoma Cell Lines

Molecules ◽

10.3390/molecules26040901 ◽

2021 ◽

Vol 26 (4) ◽

pp. 901

Author(s):

Sahar Safaee ◽

Masoumeh Fardi ◽

Nima Hemmat ◽

Neda Khosravi ◽

Afshin Derakhshani ◽

...

Keyword(s):

Cell Cycle ◽

Brain Tumor ◽

Brain Tumors ◽

Cell Lines ◽

Scratch Test ◽

Cycle Arrest ◽

U373 Cell ◽

Brain Tumor Cell ◽

Induced Apoptosis ◽

Glioma Tumors

Background: Glioma is an aggressive type of brain tumor that originated from neuroglia cells, accounts for about 80% of all malignant brain tumors. Glioma aggressiveness has been associated with extreme cell proliferation, invasion of malignant cells, and resistance to chemotherapies. Due to resistance to common therapies, glioma affected patients’ survival has not been remarkably improved. ZEB2 (SIP1) is a critical transcriptional regulator with various functions during embryonic development and wound healing that has abnormal expression in different malignancies, including brain tumors. ZEB2 overexpression in brain tumors is attributed to an unfavorable state of the malignancy. Therefore, we aimed to investigate some functions of ZEB2 in two different glioblastoma U87 and U373 cell lines. Methods: In this study, we investigated the effect of ZEB2 knocking down on the apoptosis, cell cycle, cytotoxicity, scratch test of the two malignant brain tumor cell lines U87 and U373. Besides, we investigated possible proteins and microRNA, SMAD2, SMAD5, and miR-214, which interact with ZEB2 via in situ analysis. Then we evaluated candidate gene expression after ZEB2-specific knocking down. Results: We found that ZEB2 suppression induced apoptosis in U87 and U373 cell lines. Besides, it had cytotoxic effects on both cell lines and reduced cell migration. Cell cycle analysis showed cell cycle arrest in G0/G1 and apoptosis induction in U87 and U373 cell lines receptively. Also, we have found that SAMAD2/5 expression was reduced after ZEB2-siRNA transfection and miR-214 upregulated after transfection. Conclusions: In line with previous investigations, our results indicated a critical oncogenic role for ZEB2 overexpression in brain glioma tumors. These properties make ZEB2 an essential molecule for further studies in the treatment of glioma cancer.

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Optimisation of Mechanical Properties of Gradient Zr–C Coatings

Materials ◽

10.3390/ma14020296 ◽

2021 ◽

Vol 14 (2) ◽

pp. 296

Author(s):

Łukasz Szparaga ◽

Przemysław Bartosik ◽

Adam Gilewicz ◽

Katarzyna Mydłowska ◽

Jerzy Ratajski

Keyword(s):

Adhesive Layer ◽

Scratch Test ◽

Deposition Process ◽

Functionally Graded ◽

Wear Properties ◽

Mechanical And Tribological Properties ◽

High Adhesion ◽

Graded Material ◽

Residual Stresses And Strains ◽

Optimisation Procedure

One of the key components of the designing procedure of a structure of hard anti-wear coatings deposited via Physical Vapour Deposition (PVD) is the analysis of the stress and strain distributions in the substrate/coating systems, initiated during the deposition process and by external mechanical loads. Knowledge of residual stress development is crucial due to their significant influence on the mechanical and tribological properties of such layer systems. The main goal of the work is to find the optimal functionally graded material (FGM) coating’s structure, composed of three functional layers: (1) adhesive layer, providing high adhesion of the coating to the substrate, (2) gradient load support and crack deflection layer, improving hardness and enhancing fracture toughness, (3) wear-resistant top layer, reducing wear. In the optimisation procedure of the coating’s structure, seven decision criteria basing on the state of residual stresses and strains in the substrate/coating system were proposed. Using finite element simulations and postulated criteria, the thickness and composition gradients of the transition layer in FGM coating were determined. In order to verify the proposed optimisation procedure, Zr-C coatings with different spatial distribution of carbon concentration were produced by the Reactive Magnetron Sputtering PVD (RMS PVD) method and their anti-wear properties were assessed by scratch test and ball-on-disc tribological test.

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Preparation of Soluble POSS-Linking Polyamide and Its Application in Antifogging Films

Materials ◽

10.3390/ma14123178 ◽

2021 ◽

Vol 14 (12) ◽

pp. 3178

Author(s):

Tomoya Kozuma ◽

Aki Mihata ◽

Yoshiro Kaneko

Keyword(s):

Water Vapor ◽

Heat Treating ◽

Scratch Test ◽

29Si Nmr ◽

Polar Solvents ◽

Amide Bonds ◽

Ethylcarbodiimide Hydrochloride ◽

Ft Ir ◽

Oligomeric Silsesquioxane ◽

Condensing Agents

In this study, we prepared a polyhedral oligomeric silsesquioxane (POSS)-linking polyamide (POSS polyamide) by a polycondensation of ammonium-functionalized POSS (POSS-A) and carboxyl-functionalized POSS (POSS-C) in dehydrated dimethyl sulfoxide (DMSO) using 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) as condensing agents. The obtained POSS polyamide was soluble in various highly polar solvents, and it could form a self-standing film. FT-IR, 1H NMR, and 29Si NMR analyses showed that POSS polyamide is a polymer in which POSS-A and POSS-C are linked almost linearly by amide bonds. Furthermore, the cast film obtained by heat-treating the polymer at 150 °C for 30 min exhibited excellent transparency and hard-coating (pencil scratch test: 5H) and antifogging properties (evaluation by water vapor exposure).

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Characterization of Thin Chromium Coatings Produced by PVD Sputtering for Optical Applications

Coatings ◽

10.3390/coatings11020215 ◽

2021 ◽

Vol 11 (2) ◽

pp. 215

Author(s):

Andreia A. Ferreira ◽

Francisco J. G. Silva ◽

Arnaldo G. Pinto ◽

Vitor F. C. Sousa

Keyword(s):

Automotive Industry ◽

Vapor Deposition ◽

Physical Vapor Deposition ◽

Early Stage ◽

Chemical Vapor ◽

Experimental Tests ◽

Scratch Test ◽

Industrial Sectors ◽

Deposition Processes ◽

Optical Applications

PVD (physical vapor deposition) and CVD (chemical vapor deposition) have gained greater significance in the last two decades with the mandatory shift from electrodeposition processes to clean deposition processes due to environmental, public safety, and health concerns. Due to the frequent use of coatings in several industrial sectors, the importance of studying the chromium coating processes through PVD–sputtering can be realized, investing in a real alternative to electroplated hexavalent chromium, usually denominated by chromium 6, regularly applied in electrodeposition processes of optical products in the automotive industry. At an early stage, experimental tests were carried out to understand which parameters are most suitable for obtaining chromium coatings with optical properties. To study the coating in a broad way, thickness and roughness analysis of the coatings obtained using SEM and AFM, adhesion analyzes with the scratch-test and transmittance by spectrophotometry were carried out. It was possible to determine that the roughness and transmittance decreased with the increase in the number of layers, the thickness of the coating increased linearly, and the adhesion and resistance to climatic tests remained positive throughout the study. Thus, this study allows for the understanding that thin multilayered Cr coatings can be applied successfully to polymeric substrates regarding optical applications in the automotive industry.

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Recatest—A Technique for Qualitative and Quantitative Assessment of Deferment and Degraded PVD Coatings and CVD Layers in the Deformed Area in the Scratch Test

Materials ◽

10.3390/ma14102625 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2625

Author(s):

Piotr Domanowski ◽

Marek Betiuk

Keyword(s):

Scratch Test ◽

Metallographic Analysis ◽

Tool Steels ◽

Test Device ◽

Coating Structure ◽

Testing Technique ◽

Coating Materials ◽

Qualitative And Quantitative ◽

Quantitative Parameters

The purpose of the paper is to present a new Recatest testing technique which uses a series of abrasions within a scratch and its innovative application to describe selected quantitative parameters of locally, plastically deformed substrate and coating materials detected on the spherical microsection in the scratch test. The exposed material structures are subject to a metallographic analysis which allows for the determination of the quantitative parameters, which in turn allow for a description of the change in dynamics of the coating structure within the scratch area as a function of load. These parameters include scratch depth (hs), coating thickness (h1), flash height (hoc, hos), depth of intended material (hd), material depth under scratch (hcp), and material depth under coating (hdb). The paper also includes a description of the Recalo test device designed by the authors, which is used to make a series of spherical abrasion traces on the scratch surface. Recalo is dedicated to the Recatest technique. The analysed material was the CrN/CrCN/HS6-5-2, AlCrN -Alcrona-Balinit/D2 coatings deposited on tool steels.

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Development of Elastoplastic-Damage Model of AlFeSi Phase for Aluminum Alloy 6061

Metals ◽

10.3390/met11060954 ◽

2021 ◽

Vol 11 (6) ◽

pp. 954

Author(s):

Hailong Wang ◽

Wenping Deng ◽

Tao Zhang ◽

Jianhua Yao ◽

Sujuan Wang

Keyword(s):

Aluminum Alloy ◽

Constitutive Model ◽

Material Properties ◽

Damage Model ◽

Scratch Test ◽

Aluminum Alloy 6061 ◽

Ultra Precision ◽

Simulation Results ◽

Alloy 6061 ◽

Elastoplastic Damage

Material properties affect the surface finishing in ultra-precision diamond cutting (UPDC), especially for aluminum alloy 6061 (Al6061) in which the cutting-induced temperature rise generates different types of precipitates on the machined surface. The precipitates generation not only changes the material properties but also induces imperfections on the generated surface, therefore increasing surface roughness for Al6061 in UPDC. To investigate precipitate effect so as to make a more precise control for the surface quality of the diamond turned Al6061, it is necessary to confirm the compositions and material properties of the precipitates. Previous studies have indicated that the major precipitate that induces scratch marks on the diamond turned Al6061 is an AlFeSi phase with the composition of Al86.1Fe8.3Si5.6. Therefore, in this paper, to study the material properties of the AlFeSi phase and its influences on ultra-precision machining of Al6061, an elastoplastic-damage model is proposed to build an elastoplastic constitutive model and a damage failure constitutive model of Al86.1Fe8.3Si5.6. By integrating finite element (FE) simulation and JMatPro, an efficient method is proposed to confirm the physical and thermophysical properties, temperature-phase transition characteristics, as well as the stress–strain curves of Al86.1Fe8.3Si5.6. Based on the developed elastoplastic-damage parameters of Al86.1Fe8.3Si5.6, FE simulations of the scratch test for Al86.1Fe8.3Si5.6 are conducted to verify the developed elastoplastic-damage model. Al86.1Fe8.3Si5.6 is prepared and scratch test experiments are carried out to compare with the simulation results, which indicated that, the simulation results agree well with those from scratch tests and the deviation of the scratch force in X-axis direction is less than 6.5%.

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