1、Designation: D6906 11aStandard Test Method forDetermination of Titanium Treatment Weight on MetalSubstrates by Wavelength Dispersive X-Ray Fluorescence1This standard is issued under the fixed designation D6906; the number immediately following the designation indicates the year oforiginal adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method covers the use of wavelength disper-sive X-ray fluorescence (
3、WDXRF) techniques for determina-tion of the coating weight of titanium treatments on metalsubstrates. These techniques are applicable for determinationof the coating weight as titanium or total coating weight of atitanium containing treatment, or both, on a variety of metalsubstrates.1.2 This standa
4、rd does not purport to address all of thesafety concerns, 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.2. Summary of Practice2.1 Exci
5、tationThe measurement of titanium treatmentcoating weights by WDXRF methods is based on the combinedinteraction of the titanium coating and the substrate with anintense beam of primary radiation. Since each element fluo-resces at an energy characteristic of the particular element, thisinteraction re
6、sults in the generation of X-rays of definedenergy. The primary radiation may be generated by an X-raytube or derived from a radioisotope.2.2 DetectionThe secondary beam (fluorescent X-rays ofthe elements and scattered radiation) is read by a detector thatcan discriminate between the energy levels o
7、f fluorescingradiations in the secondary beam. The detection system in-cludes the radiation detector with electronics for pulse ampli-fication and pulse counting.2.3 Basic Principle:2.3.1 A relationship exists between the treatment coatingweight and secondary radiation intensity. This relationship i
8、susually linear within the desired coating weights of thetitanium treatments on metal substrates. The measurements arebased on primary standards of known coating weights andinstrument calibration that correlates the secondary radiationintensity with the coating weight quantitatively.2.3.2 The coatin
9、g weight is determined by measurement ofthe fluorescent X-rays of the coating. The detection system isset to count the number of X-rays in an energy region that ischaracteristic of X-rays from the element of interest. Theelement of interest in this practice is titanium.2.3.3 If a linear relationship
10、 exists, the coating weight andnumber of counts of X-rays of a titanium treatment on aparticular substrate can be expressed by a conversion factorthat represents the number of counts for a particular coatingweight unit/unit area. This is usually expressed in mg/ft2ormg/m2of titanium or total coating
11、 weight.2.3.4 The exact relationship between the measured numberof counts and the corresponding coating weight must beestablished for each individual combination of substrate andtitanium-containing treatment. Usually determined by the treat-ment supplier, this relationship is established by using pr
12、imarystandards having known amounts of the same treatment appliedto the same substrate composition as the specimens to bemeasured.2.3.5 Some X-ray apparatuses have a data handling systemwhereby a coating weight versus X-ray counts curve may beestablished within the system for the direct readout of c
13、oatingweight. If such apparatus does not permit the entry of aconversion factor as described in 2.3.3, it is calibrated using abare, untreated specimen and a minimum of three specimenswith known coating weights of the treatment and substratecombination of interest. The coating weight to be measuredm
14、ust be within the range of these known coating weights. Morethan three known specimens must be used if the relationship ofX-ray counts to coating weight is not linear over the range tobe measured. The treatment supplier should be consulted forrecommendations for establishing the curve in the instrum
15、entfor the particular treatment and substrate combination ofinterest.3. Significance and Use3.1 The procedure described in this test method is designedto provide a method by which the coating weight of titaniumtreatments on metal substrates may be determined.1This test method is under the jurisdicti
16、on of ASTM Committee D01 on Paintand Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.53 on Coil Coated Metal.Current edition approved June 1, 2011. Published June 2011. Originallyapproved in 2003. Last previous edition approved in 2011 as D6906 - 11.
17、 DOI:10.1520/D6906-11A.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.3.2 This test method is applicable for determination of thetotal coating weight and the titanium coating weight of atitanium-containing treatment.4. Apparatus and
18、 Materials4.1 Measuring Instrument, which is capable of determiningthe coating weights of titanium-containing treatments on metalsubstrates by X-ray fluorescence is required. The treatmentsupplier should be consulted for the suitability of the instru-mentation to be used4.2 Calibration Standard, nec
19、essary to calibrate the instru-ment. The count value of this standard must be specified by thetreatment supplier.4.3 Treated Coupon, on which the coating weight is to bedetermined must be cut to the required size for the instrumentfrom the treated substrate.4.4 Blank (Bare and Untreated) Coupon shou
20、ld be asample of the same metal substrate on which the treatmentcoating weight is to be determined. It may be necessary toprepare a blank coupon from a treated sample if an untreatedcoupon is not available. To best imitate a bare, untreated blank,abrade a treated coupon that is from the same metal s
21、pecimenas the test specimen using a small abrasive pad.4.4.1 The first abrading is made parallel with the rollingdirection of the metal, the second abrading is made perpen-dicular to the rolling direction of the metal, and the thirdabrading is made parallel with the rolling direction of themetal. Th
22、is procedure should be repeated until constant read-ings are obtained. Always use the same side of the metalsubstrate from which the readings of the treated coupon will betaken.5. Test Specimens5.1 All test specimens must be flat in the area of measure-ment and free of burrs and distortions that wou
23、ld preventproper seating in the specimen holder.5.2 The treatment on the substrate must be uniform in thearea of measurement.5.3 The area of measurement must be maintained free offoreign materials. The specimen must be handled only by theedges that are outside of the area to be measured.5.4 The coat
24、ed area of the specimen must be larger than themeasuring area.6. Procedure6.1 Operate the instrument in accordance with the manufac-turers instructions.6.2 Set the instrument settings as follows:Dial and arm titanium positionSeconds indicator pretreatment supplierMultiplier switch pretreatment suppl
25、ierResponse switch pretreatment supplierRange pretreatment supplierMilliamps adjust for calibration of outputpretreatment supplier6.3 All specimens must be seated firmly and securely overthe measuring opening. The distance between the measuringapparatus and specimen must be maintained the same as th
26、atduring the calibration. The blank and treated specimens mustbe placed in the holder so that the rolling direction of the metalis in the same orientation. Whenever a sample tray holder is apart of the apparatus, the same opening of the slide must beused for the blank and treated specimen unless the
27、 openingshave been determined to produce equivalent results. If it isnecessary to use a backer to hold the test specimen firmlyagainst the window, make sure that the backer is of untreatedcoupons of the same metal as the specimen. The same backermust be used for each set of measurements.6.4 Insert t
28、he titanium calibration standard that has beenrecommended by the treatment supplier into the instrument,and obtain a count. Adjust the current with the control knob onthe probe until the count value is within a single significantfigure rounded approximation of 63 times the square root ofthe counts p
29、rovided by the treatment supplier with eachtitanium calibration standard.6.5 Obtain the counts of a blank.6.6 Obtain the counts of the treated specimen.6.7 Consult the instrument manufacturers instructionmanuals for calibrating and operating procedures if the X-rayapparatus has a data handling syste
30、m for direct readout ofcoating weights.7. Calculation7.1 Use 7.2-7.5 for calculating the coating weight if anautomated data handling system is not available.7.2 The average of a minimum of three readings of both theblank and treated specimen is used to calculate the coatingweight.7.3 Calculate the d
31、elta (D) counts by subtracting the countsof the blank from the counts of the treated specimen.7.4 The coating weight is calculated by dividing the Dcounts by the conversion factor that is supplied by thetreatment supplier for the particular substrate and treatmentcombination under study.Coating weig
32、ht weight/unit area! 5D countsconversion factor(1)Other methods as recommended by the treatment suppliermay be used to calculate the coating weight.7.5 The conversion factors supplied by the treatment sup-plier are valid only for the instrument calibration procedurerecommended by the treatment suppl
33、ier.8. Precision and Bias8.1 The precision and bias of this test method is beingdetermined and will be available on or before June 2012.9. Keywords9.1 coating weight; non-chrome; titanium; treatment; X-rayfluorescenceD6906 11a2ASTM International takes no position respecting the validity of any paten
34、t rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision a
35、t any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your commen
36、ts will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted
37、by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D6906 11a3
