Determination of adhesive characteristics of coatings by application a modern scratch test. Part 1. Possibilities of application a modern scratch test to determine adhesion properties of coatings.

2020 ◽  
Vol 76 (2) ◽  
pp. 143-152
Author(s):  
V. K. Belov ◽  
E. V. Gubarev ◽  
O. V. Krivko ◽  
A. V. Papshev ◽  
N. G. Gofman ◽  
...  
Keyword(s):  
Scratch Test ◽  
Ceramic Coatings ◽  
Strength Parameters ◽  
Subjective Character ◽  
Properties Of Coatings ◽  
Adhesion Properties ◽  
Power Characteristics ◽  
High Adhesion ◽  
Metal Products

At present, many kinds of metal products are produced with application of various coatings. Coatings along with requirements to provide their functional properties, must also meet additional general requirements, in particular, must have a high adhesion resistivity. Methods of direct measuring of adhesion characteristics considered. It was shown, that estimation of coatings adhesion properties by regular standard methods has a subjective character, since it is accomplished visually by specially trained laboratory assistants. Appearance of new standards and modern devices for determining of adhesion characteristics of different coatings by scratch test creates new possibilities of those properties regulation in digital form without subjective estimations. A methodology considered for determining coatings adhesion properties by application theory of scratch test. Estimation of strength parameters of the coating material depending on coating destruction character by power and geometric parameters of the deformation hearth was carried out. The relation of power characteristics of deformation hearth under indenter analyzed. Advantages and drawbacks of the scratch test quoted. It was noted, that implementation of new devices for the scratch test has required adoption of new standards for polymer and ceramic coatings. Implementation of those standards and devices for estimation of different coatings adhesion properties by application scratch test at present has no insuperable obstacles.

Scratch Test and Adhesion Properties of Titanium Coatings Deposited by TIG Welding on Steels

2015 ◽  
Vol 1111 ◽  
pp. 1-6 ◽  
Author(s):  
Elena Simona Dogar Cutean ◽  
Ion Mitelea ◽  
Viorel Aurel Şerban ◽  
Cosmin Codrean
Keyword(s):  
Scratch Test ◽  
Scratch Resistance ◽  
Substrate Material ◽  
Point Of View ◽  
Hard Coatings ◽  
Process Technology ◽  
Properties Of Coatings ◽  
Experimental Conditions ◽  
Adhesion Properties

Scratch test is one of widely used, fast, and effective methods to obtain the critical loads that are related to adhesion properties of coatings. The determination of adhesion and the scratch resistance is essential for the mechanical characterization of surface layers for research and industry. To evaluate the performance of coatings the scratch test with a Rockwell-C diamond stylus as indenter is a commonly used test for the characterization of hard coatings on predominant metallic substrates due to its comparatively robust experimental setup, the easy use and the representative results. This is the only technique capable of imaging such interface defects which are due to the stressin duced by the scratch experiment.This paper aims to characterize the adhesion and scratch resistance using Millennium200 - Technical Tribo equipment of Ti layer deposited on steel surfaces by means of TIG/WIG welding technique. Ensuring appropriate functional properties of WIG welding coatings (Ti) requires a good compatibility with the substrate material (S235). For this reason was used to deposit titanium WIG welding an intermediary layer of copper, obtained in the same experimental conditions. The optimal selection of the coating material takes into consideration the metallurgical, mechanical and process technology compatibility. The mechanical properties of coatings must match the substrate. From this point of view, maintaining a high corrosion resistance is mainly conditioned by achieving a good adhesion and a microstructure free of internal cracks or other defects.

Influence of Tin-Chloride Pretreatment on Mirror Coating Adhesion

2005 ◽  
Vol 473-474 ◽  
pp. 465-470 ◽  
Author(s):  
A. Nagy ◽  
Norbert Hegman
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Glass Surface ◽  
Scratch Test ◽  
Float Glass ◽  
Properties Of Coatings ◽  
Adhesion Properties ◽  
Tin Chloride ◽  
Scratch Track ◽  
Scanning Electron

Our research focused on the adhesion properties of mirror coating on silica float glass due to applying different quantity of tin-chloride sensitizing agent. Investigation was carried out to detect the distribution and quantity of tin containing clusters deposited on the glass surface working as crystallization centre. The adhesion properties of coatings were tested by scratch test where critical peeling forces were evaluated. The morphology of the formed scratch track was measured with scanning electron microscope. The surface topography was scanned by AFM technique.

scholarly journals Optimisation of Mechanical Properties of Gradient Zr–C Coatings

Materials ◽  
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.

scholarly journals 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 ◽  
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.

scholarly journals Preliminary research for identification of bacteria useful in microbially induced calcium carbonate precipitation

2018 ◽  
Vol 44 ◽  
pp. 00115
Author(s):  
Katarzyna Misiołek ◽  
Paweł Popielski ◽  
Katarzyna Affek
Keyword(s):  
Calcium Carbonate ◽  
Soil Stabilization ◽  
Carbonate Precipitation ◽  
Calcium Carbonate Precipitation ◽  
Construction Sites ◽  
Calcite Precipitation ◽  
Strength Parameters ◽  
Gram Staining ◽  
Identification Of Bacteria

MICP (Microbially Induced Calcite Precipitation) is a new biological method in soil stabilization. This cheap and eco-friendly technique improves strength parameters of the ground such as shear strength and decreases the permeability of gravelly and sandy soil. There are variety of microorganisms that can be used in calcite precipitation. The most popular method is precipitation of calcium carbonate by bacteria. The main purpose of the article is to present the results from Gram staining of bacteria isolated from construction sites, which is the first step of their identification. Gram’s method allows to find out which morphological groups of bacteria are adapted to conditions present in soil from construction sites and therefore are potentially able to produce calcite. The article describes the methodology of isolation, staining and determination of morphological types of bacteria.

Determination of Residual Stresses in Multimaterial, Multilayer Pieces — Adaptation to Ceramic Coatings

CIRP Annals ◽  
1991 ◽  
Vol 40 (1) ◽  
pp. 535-539 ◽  
Author(s):  
M. Laracine ◽  
C. Bignon ◽  
M. Lormand ◽  
A.B. Vannes ◽  
C. Bedrin
Keyword(s):  
Residual Stresses ◽  
Ceramic Coatings

scholarly journals Production of modified adhesive composites based on EVA and modified PE

2020 ◽  
pp. 45-47
Author(s):  
M. D. Sizova ◽  
A. N. Zelenetsky ◽  
V. Ya. Ivolgin
Keyword(s):  
Maleic Anhydride ◽  
Polymer Matrix ◽  
Morphological Changes ◽  
Adhesive Properties ◽  
Adhesion Properties ◽  
High Adhesion

An adhesive based on EVA and LDPE is developed which can be used up to 60°C. It was modified by polyisocyanate fragments of a grafted and reticulate nature for structural and morphological changes of the polymer matrix and improvement of physical, mechanical and adhesive properties. For additional compatibilization of the components, LDPE modified with maleic anhydride (MA) was used. High adhesion properties of the obtained composites were confirmed.

scholarly journals Determination of Equivalent Mohr-Coulomb Criterion from Generalised Hoek-Brown Criterion

2021 ◽  
Author(s):  
Qingqing Yang ◽  
Fei Cai
Keyword(s):  
Principal Stress ◽  
Least Squares Method ◽  
Method Comparison ◽  
Friction Angle ◽  
Engineering Practice ◽  
Shear Strength Parameters ◽  
Strength Parameters ◽  
Coulomb Criterion ◽  
Minor Principal Stress

Abstract A new analytical solution is presented for determining equivalent Mohr-Coulomb (MC) shear strength parameters over an arbitrary interval of minor principal stress σ3 from the generalised Hoek-Brown (HB) criterion using least squares method. Comparison with several published examples demonstrates that the proposed solution had a capacity to accurately determine equivalent MC parameters over a given interval of σ3, as well as instantaneous MC parameters by using a very small interval of σ3. EMC parameters depended heavily on the interval of σ3, which highlighted the importance of intervals of σ3. A calculation case shows that the equivalent internal friction angle and cohesion over the interval of σ3 from tension cut-off σcut−off to maximum minor principal stress σ3max were approximately 12% smaller and 10.3% larger than those over an interval from tensile strength to σ3max, respectively. The proposed solution offers great flexibility for the application of the HB criterion with existing methods based on the MC criterion for rock engineering practice.

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