1、Designation: D6906 11Standard Test Method forDetermination of Titanium Treatment Weight on MetalSubstrates by X-Ray Fluorescence1This standard is issued under the fixed designation D6906; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revis
2、ion, 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 X-ray fluorescence(XRF) techniques for determination of the coatin
3、g weight oftitanium treatments on metal substrates. These techniques areapplicable for determination of the coating weight as titaniumor total coating weight of a titanium containing treatment, orboth, on a variety of metal substrates.1.2 This standard does not purport to address all of thesafety co
4、ncerns, 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 ExcitationThe measurement of titanium treatmentcoating
5、 weights by XRF 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 results in the generation of X-rays of definedenergy.
6、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 of fluorescingradiations in the secondary beam. The d
7、etection 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 isusually linear within the desired coating weights o
8、f 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 coating weight is determined by measurement ofthe fluoresc
9、ent 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 exists, the coating weight andnumber of counts of X
10、-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 weight.2.3.4 The exact relationship between the mea
11、sured 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 primarystandards having known amounts of the same trea
12、tment 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 coatingweight. If such apparatus does not permit the
13、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 measuredmust be within the range of these known coating weigh
14、ts. 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 instrumentfor the particular treatment and substrate combin
15、ation 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 jurisdiction of ASTM Committee D01 on Paintand Related Coating
16、s, Materials, and Applications and is the direct responsibility ofSubcommittee D01.53 on Coil Coated Metal.Current edition approved Feb. 1, 2011. Published February 2011. Originallyapproved in 2003. Last previous edition approved in 2010 as D6906 - 03 (2010)1.DOI: 10.1520/D6906-11.1Copyright ASTM In
17、ternational, 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 Materials4.1 Measuring Instrument, which
18、 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, necessary to calibrate the instru-ment. The
19、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 should be asample of the same metal substrate
20、 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 specimenas the test specimen using a small
21、 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. This procedure should be repeated until con
22、stant 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 would preventproper seating in the specimen
23、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 coated area of the specimen must be larger th
24、an 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 supplierResponse switch pretreatment supplierR
25、ange 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 thatduring the calibration. The blank and t
26、reated 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 openingshave been determined to produce
27、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 the titanium calibration standard that has
28、 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 provided by the treatment supplier with ea
29、chtitanium 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 system for direct readout ofcoating weights.7.
30、 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 delta (D) counts by subtracting the counts
31、of 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 weight weight/unit area! 5D countsconversion
32、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 supplier.8. Precision and Bias8.1 The precisio
33、n 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 112ASTM International takes no position respecting the validity of any patent rights asserted in connection with any i
34、tem 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 at any time by the responsible technical co
35、mmittee 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 comments will receive careful consideration at a
36、 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 by ASTM International, 100 Barr Harbor Dri
37、ve, 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 113
