1、Designation: C 1624 05Standard Test Method forAdhesion Strength and Mechanical Failure Modes ofCeramic Coatings by Quantitative Single Point ScratchTesting1This standard is issued under the fixed designation C 1624; the number immediately following the designation indicates the year oforiginal adopt
2、ion or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the determination of the prac-tical adhesion str
3、ength and mechanical failure modes of hard(Vickers Hardness HV = 5 GPa or higher), thin (#30 m)ceramic coatings on metal and ceramic substrates at ambienttemperatures. These ceramic coatings are commonly used forwear/abrasion resistance, oxidation protection, and functional(optical, magnetic, electr
4、onic, biological) performance im-provement.1.2 In the test method, a diamond stylus of defined geometry(Rockwell C, a conical diamond indenter with an includedangle of 120 and a spherical tip radius of 200 m) is drawnacross the flat surface of a coated test specimen at a constantspeed and a defined
5、normal force (constant or progressivelyincreasing) for a defined distance. The damage along thescratch track is microscopically assessed as a function of theapplied force. Specific levels of progressive damage areassociated with increasing normal stylus forces. The forcelevel(s) which produce a spec
6、ific type/level of damage in thecoating are defined as a critical scratch load(s).The test methodalso describes the use of tangential force and acoustic emissionsignals as secondary test data to identify different coatingdamage levels.1.3 Applicability to CoatingsThis test method is appli-cable to a
7、 wide range of hard ceramic coating compositions:carbides, nitrides, oxides, diamond, and diamond-like carbonon ceramic and metal substrates. The test method, as definedwith the 200 m radius diamond stylus, is commonly used forcoating thicknesses in the range of 0.1 to 30 m. Testspecimens generally
8、have a planar surface for testing, butcylinder geometries can also be tested with an appropriatefixture.1.4 Principal Limitations:1.4.1 The test method does not measure the fundamentaladhesion strength of the bond between the coating and thesubstrate. Rather, the test method gives an engineering mea
9、-surement of the practical (extrinsic) adhesion strength of acoating-substrate system, which depends on the complexinteraction of the test parameters (stylus properties and geom-etry, loading rate, displacement rate, and so forth) and thecoating/substrate properties (hardness, fracture strength, mod
10、u-lus of elasticity, damage mechanisms, microstructure, flawpopulation, surface roughness, and so forth).1.4.2 The defined test method is not directly applicable tometal or polymeric coatings which fail in a ductile, plasticmanner, because plastic deformation mechanisms are verydifferent than the br
11、ittle damage modes and features observedin hard ceramic coatings. The test method may be applicable tohard metal coatings which fail in a brittle mode with appro-priate changes in test parameters and damage analysis proce-dures and criteria.1.4.3 The test method, as defined with the Rockwell Cdiamon
12、d stylus and specific normal force and rate parameters,is not recommended for very thin (30 m). Such coatings may require different stylus geom-etries, loading rates, and ranges of applied normal force forusable, accurate, repeatable results.1.4.4 The values stated in SI units are to be regarded ass
13、tandard. No other units of measurement are included in thisstandard. Test data values in SI units (newtons (N) for forceand millimetres (mm) for displacement) are to be considered asstandard and are in accordance with IEEE/ASTM SI 10.1.4.5 This standard does not purport to address all of thesafety c
14、oncerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.1.5 OrganizationThe test method is organized into thefollowing sections:Section
15、Scope 1Purpose and Description 1.1Applicability 1.3Principal Limitations 1.4Organization 1.5Referenced Documents 2ASTM Standards 2.1Other Standards and References 2.2Terminology 3Summary of Test Method 41This test method is under the jurisdiction of ASTM Committee C28 onAdvanced Ceramics and is the
16、direct responsibility of Subcommittee C28.01 onMechanical Properties and Performance.Current edition approved June 1, 2005. Published June 2005.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.SectionSignificance and Use 5Test Methodo
17、logy and Experimental Control 6Test Overview 6.1Test Modes 6.2Primary and Supplementary Measurements 6.3Critical Scratch Load Damage Criteria and Scratch Atlas 6.4Experimental Factors and Variables 6.5Interferences 7Material and Specimen Related 7.2Test Method Related 7.3Apparatus 8General Descripti
18、on 8.1Stylus and Stylus Mounting 8.2Mechanical Stage and Displacement Control 8.3Test Frame and Force Application System 8.4Force and Displacement Sensors 8.5Optical Analysis and Measurement 8.6Data Acquisition and Recording 8.7Acoustic Emission (Optional) 8.8Coating Adhesion Reference Specimens (Op
19、tional) 8.9Coating Surface Profilometry (Optional) 8.10Data Analysis and Output Software (Optional) 8.11Test Specimens 9Specimen Requirements 9.1Specimen Characterization 9.2Specimen Size 9.3Specimen Flatness and Level 9.4Polishing (Optional) 9.5Specimen Exposure Conditioning (Optional) 9.6Specimen
20、Cleaning 9.7Specimen Handling and Storage 9.8Calibration 10System Calibration 10.1Reference Specimens 10.2Test Procedure 11Calibration 11.1Test Mode Selection 11.2Test Planning 11.3Stylus Inspection and Cleaning 11.4Environmental Conditions 11.5System Set-Up and Check 11.6Test Specimen Mounting 11.7
21、Conducting the Test 11.8Specimen Count 11.9Invalid and Censored Data 11.10Scratch Damage Assessment 11.11Calculations 12Report 13Test Identification 13.2Specimen Information 13.3Test Equipment and Procedure Information 13.4Test Data and Statistics 13.5Precision and Bias 14Keywords 15Rockwell Diamond
22、 Indenter Specifications Annex A1Alignment and Calibration Annex A2Repeatability and Reproducibility Studies Annex A3Coating Damage Criteria and Scratch Atlas Appendix X1Experimental Variables in Scratch Adhesion Testing Appendix X2Bibliography2. Referenced Documents2.1 ASTM Standards:2B 659 Guide f
23、or Measuring Thickness of Metallic andInorganic CoatingsE4 Practices for Force Verification of Test MachinesE18 Test Methods for Rockwell Hardness and RockwellSuperficial Hardness of Metallic MaterialsE 750 Practice for CharacterizingAcoustic Emission Instru-mentationE 1316 Terminology for Nondestru
24、ctive TestingE 1932 Guide for Acoustic Emission Examination of SmallPartsIEEE/ASTM SI 10 Standard for Use of the InternationalSystem of Units (SI) (The Modern Metric System)2.2 ASME Standard:3ASME B46.1 Surface Texture (Surface Roughness, Wavi-ness, and Lay)2.3 CEN Standard:4CEN prEN 1071-3 Advanced
25、 Technical CeramicsMethods of Test for Ceramic CoatingsPart 3: Determi-nation Of Adhesive And Other Mechanical Failure ModesBy A Scratch Test3. Terminology3.1 Definitions:3.1.1 acoustic emission, nclass of phenomenon in whichelastic waves are generated by the rapid release of energy fromlocalized so
26、urces within a material, or the transient waves sogenerated. E 13163.1.2 adhesive failure, ndetachment and separation of acoating from the substrate with cracking and debonding at thecoating-substrate interface.3.1.3 cohesive failure, nmaterial damage and cracking inthe coating or in the substrate,
27、separate and distinct fromdetachment and adhesive debonding at the coating-substrateinterface.3.1.4 critical scratch load (LCN), napplied normal force atwhich a specific, well-defined, recognizable damage/failureevent occurs or is observed in the scratch test of a specificcoating on a specific subst
28、rate.3.1.4.1 DiscussionThe subscript N is used to identifyprogressive failure events. For example, LC1is often used toidentify the first level of cohesive failure in the coating itself;LC2is often used to identify first adhesive failure between thecoating and the substrate. Multiple subscripts can b
29、e used forprogressive levels of distinct damage in a specific coating-substrate systems.3.1.5 fundamental adhesion, nsummation of all interfa-cial intermolecular interactions between a film or coating andits substrate.3.1.6 normal force (LN), nin a scratch test, the forceexerted by the stylus, perpe
30、ndicular to the test surface of thetest specimen.3.1.7 practical adhesion, nforce or work required toremove or detach a film or coating from its substrate irrespec-tive of the locus of failure.3.1.7.1 Discussion“Practical adhesion” is a test conceptwhich uses various engineering coating adhesion tes
31、t methodsto obtain a quantitative, reproducible adhesion measurementwhich can be related to the functional performance of the2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information,
32、refer to the standards Document Summary page onthe ASTM website.3Available from American Society of Mechanical Engineers (ASME), ASMEInternational Headquarters, Three Park Ave., New York, NY 10016-5990, www.as-me.org.4Available from European Committee for Standardization (CEN), 36 rue deStassart, B1
33、050 Brussels, www.cenorm.be.C1624052coating. The practical adhesion is an extrinsic property whichdepends on the complex interaction of coating/substrate prop-erties and characteristics with the specific test parameters.3.1.8 stylus drag coeffcient, nin scratch testing, the di-mensionless ratio of t
34、he tangential force to the normal forceapplied to the stylus at a specific point in the scratch test.3.1.8.1 DiscussionThe term stylus drag coefficient ispreferred to the more common term scratch coefficient offriction (SCF). The tangential force is primarily a measure ofthe perpendicular force requ
35、ired to plow the indenter throughthe coating, rather than to slide it on the surface (slidingfriction is a relatively minor contribution to the measuredtangential force unless penetration is very small and surfaceproperties dominate). Thus the term friction coefficient is notappropriate for these st
36、ylus scratch tests. The SCF term is tooeasily misunderstood or misused as a measurement of slidingfriction.3.1.9 tangential force (LT), nforce that opposes the rela-tive motion between a moving stylus and the surface that isbeing scratched by the stylus and which is perpendicular to thenormal force
37、exerted by the stylus (also called the frictionforce, drag force, or the scratching force).4. Summary of Test Method4.1 This test consists of producing and assessing controlleddamage in a hard ceramic coating by single point scratch action(see Fig. 1). The scratch is developed on a coated test speci
38、menby drawing a diamond stylus of defined geometry and tip size(Rockwell C, 200 m radius) across the flat surface of thespecimen at a constant speed and a controlled and measurednormal force (constant or progressively increasing). Withincreasing applied normal force, the stylus produces progres-sive
39、 mechanical damage in the coating and the substratethrough the complex combination of elastic/plastic indentationstresses, frictional forces, and residual internal stresses in thecoating/substrate system (Fig. 2).4.2 The specific levels and types of progressive damage inthe scratch track are assesse
40、d and associated with the appliednormal stylus forces. The normal force which produces aspecific, defined, reproducible type/level of damage is definedas a critical scratch load (LC). For a given coating-substratesystem, one or more different critical scratch loads (LCN) canbe defined for progressiv
41、e levels of defined coating damage.4.3 Coating damage is assessed by optical microscopy orscanning electron microscopy, or both, during or after thescratch test is done. The tangential force and acoustic emissionsignals can also be measured and recorded during the scratchtest process and used as sup
42、plementary test data to identifydifferent coating damage levels. In commercial instruments,computerized electronic systems are commonly used to apply,control, measure, and record the force signals and acousticemission signals and to control the stylus-specimen movement.4.4 The two primary modes of s
43、cratch adhesion testing areconstant load and progressive load. In constant load (CL)scratch testing, the normal force on the stylus is maintained ata constant level as the stylus moves in relation to the testspecimen surface. Sequential scratch tests are done at increas-ing force increments to deter
44、mine the critical scratch load fora given damage level.NOTE 1Test systems may have either a movable stage or a movablestylus with the alternate component in a fixed position.4.5 In progressive load (PL) scratch tests, the applied stylusforce is linearly increased to a defined maximum force as thesty
45、lus moves in relation to the test specimen surface.4.6 The critical scratch loads at which a defined coatingfailure event occurs depend on a complex interaction ofcoating-substrate properties and test parameters/conditions. Itis the purpose of this test standard to: (1) describe and definethe test e
46、quipment and procedures and the major and minorcoating-substrate properties which have to be controlled, mea-sured, and understood to produce reliable, comparable coatingadhesion test data, and (2) define a report format that willprovide complete and accurate test data.5. Significance and Use5.1 Thi
47、s test is intended to assess the mechanical integrity,failure modes, and practical adhesion strength of a specifichard ceramic coating on a given metal or ceramic substrate.The test method does not measure the fundamental “adhesionstrength” of the bond between the coating and the substrate.Rather, t
48、he test method gives a quantitative engineering mea-surement of the practical (extrinsic) adhesion strength andFIG. 1 Test Method SchematicFIG. 2 Schematic Example of Progressive Damage in ScratchTrack in a Progressive Load Scratch TestC1624053damage resistance of the coating-substrate system as a f
49、unctionof applied normal force. The adhesion strength and damagemodes depend on the complex interaction of the coating/substrate properties (hardness, fracture strength, modulus ofelasticity, damage mechanisms, microstructure, flaw popula-tion, surface roughness, and so forth) and the test parameters(stylus properties and geometry, loading rate, displacementrate, and so forth).5.2 The quantitative coating adhesion scratch test is asimple, practical, and rapid test. However, reliable and repro-ducible test results require careful control of the test systemconfi
