1、BRITISH STANDARD BS EN 14205:2003 Natural stone test methods Determination of Knoop hardness The European Standard EN 14205:2003 has the status of a British Standard ICS 73.020; 91.100.15 BS EN 14205:2003 This British Standard, was published under the authority of the Standards Policy and Strategy C
2、ommittee on 10 December 2003 BSI 10 December 2003 ISBN 0 580 43036 7 National foreword This British Standard is the official English language version of EN 14205:2003. The UK participation in its preparation was entrusted to Technical Committee B/545, Natural stone, which has the responsibility to:
3、A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International St
4、andards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Stand
5、ard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and Europea
6、n developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 9 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publ
7、ication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN14205 November2003 ICS73.020;91.100.15 Englishversion NaturalstonetestmethodsDeterminationofKnoophardness Mthodesdessaipourlespierresnaturelles DterminationdeladuretKnoop PrfverfahrenfrNatursteinBestimmungderHrtenach Knoo
8、p ThisEuropeanStandardwasapprovedbyCENon1September2003. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standards
9、maybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official ve
10、rsions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,Germany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORM
11、ALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN14205:2003EEN14205:2003(E) 2 Contents page Foreword3 1 Scope 4 2 Principle4 3 Symbols 4 4 Apparatus .4 5 Prepara
12、tionofthespecimens .4 5.1 Sampling.4 5.2 Numberofspecimens . 4 6 Testprocedure .5 7 Expressionofresults . .6 8 Testreport . .6EN14205:2003(E) 3 Foreword Thisdocument(EN14205:2003)hasbeenpreparedbyTechnicalCommitteeCEN/TC246,“Naturalstones“,the secretariatofwhichisheldbyUNI. ThisEuropeanStandardshall
13、begiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbyMay2004,andconflictingnationalstandardsshallbewithdrawnatthelatestby May2004. Thisstandardisoneoftheseriesofstandardsfortestsonnaturalstone. Testmethodsfornaturalstoneconsistofthefollowingparts: EN1
14、925, NaturalstonetestmethodsDeterminationofwaterabsorptioncoefficientbycapillarity EN1926, NaturalstonetestmethodsDeterminationofcompressivestrength EN1936, NaturalstonetestmethodsDeterminationofrealdensityandapparentdensityandoftotalandopen porosity EN12370, NaturalstonetestmethodsDeterminationofre
15、sistancetosaltcrystallisation EN12371, NaturalstonetestmethodsDeterminationoffrostresistance EN12372, NaturalstonetestmethodsDeterminationofflexuralstrength underconcentratedload EN12407, NaturalstonetestmethodsPetrographicexamination EN13161, NaturalstonetestmethodsDeterminationofflexuralstrengthun
16、derconstantmoment EN13755, NaturalstonetestmethodsDeterminationofwaterabsorptionatatmosphericpressure EN13373, NaturalstonetestmethodsDeterminationofgeometriccharacteristicsonunits EN13919, NaturalstonetestmethodsDeterminationofresistancetoageingbySO 2 actioninthepresenceof humidity EN14066, Natural
17、stonetestmethodsDeterminationofresistancetoageingbythermalshock prEN14147, NaturalstonetestmethodsDeterminationofresistancetoageingbysaltmist prEN14157, NaturalstonetestmethodsDeterminationoftheabrasionresistance prEN14158, NaturalstonetestmethodsDeterminationofruptureenergy prEN14231, Naturalstonet
18、estmethodsDeterminationoftheslipresistancebymeansofthependulumtester prEN14581, NaturalstonetestmethodsDeterminationofthermalexpansioncoefficient prEN14579, NaturalstonetestmethodsDeterminationofsoundspeedpropagation prEN14580, NaturalstonetestmethodsDeterminationofthestaticelasticmodulus Noexisting
19、EuropeanStandardissuperseded. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, France,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,
20、Norway,Portugal, Slovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN14205:2003(E) 4 1Scope ThisEuropeanStandardspecifiesamethodofdeterminingthehardnessofmineralsinnaturalstoneusingthe Knoopindenter.Thismethodisespeciallyusefulforcarbonaterock. 2Principle Aftercarryingoutaseriesofindentationsbyme
21、ansofaKnoopindenter,thecorrespondingvaluesofKnoop microhardnessarecalculatedandthemicrohardnessdistributionisgiven. 3Symbols P loadontheindenter,innewtons L lengthofthelargestdiagonaloftheindentation,inmillimetres HK Knoopmicrohardness,inMegapascals HK25Knoopmicrohardnesscorrespondingtoacumulativefr
22、equencyof25%(“lowerquartile”),in Megapascals HK50Knoopmicrohardnesscorrespondingtoacumulativefrequencyof50%(“medianvalue”) HK75Knoopmicrohardnesscorrespondingthecumulativefrequencyof75%(“upperquartile”) 4Apparatus Amicrodurimeteressentiallymadeofthefollowingparts: sampleholderwithamechanismforhorizo
23、ntalmovementintwoorthogonaldirectionsbymeansofadjustable screwswhichalsomeasuretheamountofmovement; Knoopindenter(seeFigure1); setofinterchangeableweightsfrom(0,1to5,0)Newtons; deviceforapplyingtheloadontheindenteratdifferentspeeds; microscopewithamicrometerformeasuringtheindentationwidthandlengthwi
24、thanaccuracyof0,5 micrometres. 5 Preparationofthespecimens 5.1Sampling Thesamplingisnottheresponsibilityofthetestlaboratoryexceptwherespeciallyrequested. 5.2 Numberofspecimens Atleastonepolishedsectionshallbepreparedapproximately20mmwidth,30mmlengthand10mmthickness. Othersizesmaybeusedprovidedthatth
25、ereisenoughspaceonthepolishedfacetocarryoutthenecessary sequenceofindentations.EN14205:2003(E) 5 Inthecaseofstonesshowinganisotropyplanes(e.g.bedding,foliation)atleasttwopolishedsectionsshallbe prepared:onewiththepolishedfaceparalleltotheanisotropyplanesandtheotherperpendicular. Inthecaseofveryinhom
26、ogeneouscoarsegrainedstones,itisnecessarytopreparealargersectionthanthe previouslydescribedoneoralternatively,touseseveralsectionsofstandarddimensions(sothatforthespecimen besufficientlyrepresentative). 6 Testprocedure Thetestconsistsofcarryingout: 20indentations,inlineandwith1mmbetweenthem,forfineg
27、rained,visiblyuniformtypesofstone; threeseries(20+10+10)ofindentationsforheterogeneous,mediumgrainedorcoarsegrainedstone;ineach seriesthedistancebetweentheindentationswillbe1mm; eightseriesof10indentationeachforveryheterogeneousorverycoarsegrainedstones;ineachseriesthe distancebetweentheindentations
28、hallbenotlessthan2mm. Proceedasfollows: 1) placethechosenweight(see4)onthetraytoapplytheload; NOTE1 Theloadappliedisequalforalltypesofrock(therecommendedloadis1,96Nsincethiscreatesindentationsthat aremeasurableinbothhardandsoftrocks). 2) positionthespecimenonthesampleholderandfocusbymeansofthemicros
29、copelens; 3) usethetwodirectionalstageholdertobringthepointchosenasthefirstpointoftherandomsequenceof20 alignedindentationstothecentreofthefield.Forvisiblyanisotropicstones,chooseanalignmentperpendicular totheplanesofanisotropy; 4) rotatethelenstobringtheindenteroverthefirstpointofthesequenceandacti
30、vatetheindentersautomatic descentmechanism; NOTE2 Thespeedatwhichtheloadisappliedisthesameforalltypesofrock(therecommendedspeedisthatatwhich completeapplicationoftheloadof1,96Nisachievedin40s). 5) oncetheloadhasbeenapplied,lifttheindenter,rotatethelensintotheoperatingpositionandthenmeasure thelength
31、ofthelargestdiagonaloftheindentationbymeansofthegraduatedscaleofthemicroscope; 6) usingthetwodirectionalstageholder,movethesampleholderonemillimetreinthedirectionchosenforthe alignmentofthemeasurements:theindenterisnowinpositionforthesecondpoint.Forvisuallyuniformfine grainedstonesrepeattheaboveoper
32、ationsuntil20indentationshavebeenmadeandmeasured; NOTE3 Inordertoavoidnonrandom(i.e.“unconsciouslyintentional”)positioning,movethesampleholderindenter1mm betweenonemeasurementandthenextwithoutlookingthroughthemicroscope. 7) inthecaseofheterogenous,mediumgrainedorcoarsegrainedstones,carryoutanothertw
33、oseriesof10 measurements,still1mmapart,inanydirectiondifferentfromtheinitialone(foratotalof40indentations); 8) inthecaseofveryheterogeneousorverycoarsegrainedstones,itisnecessarytocarryoutanothersetof40 indentationsonatleastanotherspecimenoronthesamespecimen(ifapolishedsectionoflargerdimensions isus
34、ed).Inbothcasesthedistancebetweentheindentationsshallbenotlessthan2mm.EN14205:2003(E) 6 7 Expressionofresults ForeachindentationKnoophardness HK (inMPa)isexpressedbymeansofthefollowingformula: 2 23 , 14 L P HK = (1) where: Pistheloadontheindenter,inNewtons; Listhelengthofthelargestdiagonaloftheinden
35、tationleftbytheindenter,inmillimetres. Thehardnessvaluesobtainedarearrangedinincreasingorderandareplottedagainsttheorderofrank.The abscissascalecanalsobegraduatedinpercentages:thisgivesadiagramofthecumulativefrequencyofthe microhardnessvaluesofthestone(“hardnessdistributiondiagram”,seeFigure2).Thepa
36、rtsofthediagramparallel (orsubparallel)totheabscissaindicatecontentsofthecomponentswithwelldefinedhardnessvalues,whereas slopingpartsofthediagramindicatethecontentsofthecomponentswithhardnessvaluesthatvarygradually betweentwoextremes. Thehardnessdistributiondiagramgivesaverydetailedinformationonston
37、ehardness;however,forcomparison purposes,amoresyntheticexpressionoftheresultsisneeded,makingreferencetothefollowingcharacteristic values(seeFigure2): microhardnessvaluecorrespondingtothecumulativefrequencyof25%( HK25or“lowerquartile“); microhardnessvaluecorrespondingtothecumulativefrequencyof50%( HK
38、50or“medianvalue“); microhardnessvaluecorrespondingtothecumulativefrequencyof75%( HK75or“upperquartile“). NOTE Theratiobetween HK75and HK25providesanindicationontheuniformityofthestonefrompointofviewofthe hardness:thenearertheratioisto1,themoreuniformthestone. 8 Testreport Thetestreportshallcontaint
39、hefollowinginformation: a) uniqueidentificationnumberofthereport; b) number,titleanddateofissueofthisEuropeanStandard; c) nameandaddressofthetestlaboratoryandtheaddresswherethetestwascarriedoutifdifferentfromthe testlaboratory; d) nameandaddressoftheclient; e) itistheresponsibilityoftheclienttosuppl
40、ythefollowinginformation: petrographicnameofthestone; commercialnameofthestone; countryandregionofextraction; nameofthesupplier;EN14205:2003(E) 7 directionofanyexistingplaneofanisotropy(ifrelevanttothetest)tobeclearlyindicatedonthesampleoron eachspecimenbymeansoftwoparallellines; nameofthepersonoror
41、ganizationwhichcarriedoutthesampling; surfacefinishofthespecimens(ifrelevanttothetest). f) dateofdeliveryofthesampleorofthespecimens; g) datewhenthepolishessection(s)werepreparedandthedateoftesting; h) numberandthedimensionsofthepolishedsections; i) orientationofthepolishedfaceofeachsectionwithrespe
42、cttotheanisotropyplanes; j) loadappliedontheindenterandtheloadapplicationrate; k)individual microhardness values HK,calculatedonthebasisofthesequenceof20or40or80measurements, andthecumulativefrequencydiagram(“hardnessdistributiondiagram”); l) meanvalueoftheindividualmicrohardnessvalues( HK ); m)char
43、acteristic microhardness values: HK25 (lowerquartile), HK50(meadianvalue), HK75(upperquartile); n) alldeviationsfromthestandardandtheirjustification; o) remarks. Thetestreportshallcontainthesignature(s)androle(s)oftheresponsible(s)forthetestingandthedateofissueof thereport.Itshallalsostatethatthereportshallnotbepartiallyreproducedwithoutthewrittenconsentofthetest la
