ASTM D6906 – 03

Designation: D 6906 – 03 Standard Test Method for Determination of Titanium Treatment Weight on Metal Substrates by X-Ray Fluorescence1 This standard is issued under the fixed designation D 6906; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscript epsilon (e) indicates an editorial change since the last revision or reapproval. 1. Scope 1.1 This test method covers the use of X-ray fluorescence (XRF) techniques for determination of the coating weight of titanium treatments on metal substrates. These techniques are applicable for determination of the coating weight as titanium or total coating weight of a titanium containing treatment, or both, on a variety of metal substrates. 1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility 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 Practice 2.1 Excitation—The measurement of titanium treatment coating weights by XRF methods is based on the combined interaction of the titanium coating and the substrate with an intense beam of primary radiation. Since each element fluo- resces at an energy characteristic of the particular element, this interaction results in the generation of X-rays of defined energy. The primary radiation may be generated by an X-ray tube or derived from a radioisotope. 2.2 Detection—The secondary beam (fluorescent X-rays of the elements and scattered radiation) is read by a detector that can discriminate between the energy levels of fluorescing radiations 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 coating weight and secondary radiation intensity. This relationship is usually linear within the desired coating weights of the titanium treatments on metal substrates. The measurements are based on primary standards of known coating weights and instrument calibration that correlates the secondary radiation intensity with the coating weight quantitatively. 2.3.2 The coating weight is determined by measurement of the fluorescent X-rays of the coating. The detection system is set to count the number of X-rays in an energy region that is characteristic of X-rays from the element of interest. The element of interest in this practice is titanium. 2.3.3 If a linear relationship exists, the coating weight and number of counts of X-rays of a chromium treatment on a particular substrate can be expressed by a conversion factor that represents the number of counts for a particular coating weight unit/unit area. This is usually expressed in mg/ft2 or mg/m2 of titanium or total coating weight. 2.3.4 The exact relationship between the measured number of counts and the corresponding coating weight must be established for each individual combination of substrate and titanium-containing treatment. Usually determined by the treat- ment supplier, this relationship is established by using primary standards having known amounts of the same treatment applied to the same substrate composition as the specimens to be measured. 2.3.5 Some X-ray apparatuses have a data handling system whereby a coating weight versus X-ray counts curve may be established within the system for the direct readout of coating weight. If such apparatus does not permit the entry of a conversion factor as described in 2.3.3, it is calibrated using a bare, untreated specimen and a minimum of three specimens with known coating weights of the treatment and substrate combination of interest. The coating weight to be measured must be within the range of these known coating weights. More than three known specimens must be used if the relationship of X-ray counts to coating weight is not linear over the range to be measured. The treatment supplier should be consulted for recommendations for establishing the curve in the instrument for the particular treatment and substrate combination of interest. 3. Significance and Use 3.1 The procedure described in this test method is designed to provide a method by which the coating weight of titanium treatments on metal substrates may be determined.1 This test method is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility of Subcommittee D01.53 on Coil Coated Metal. Current edition approved May 10, 2003. Published June 2003. 1 Copyright © 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 the total coating weight and the titanium coating weight of a titanium-containing treatment. 4. Apparatus and Materials 4.1 Measuring Instrument,2 which is capable of determining the coating weights of chromium-containing treatments on metal substrates by X-ray fluorescence is required. The treat- ment supplier should be consulted for the suitability of the instrumentation to be used 4.2 Calibration Standard,3 necessary to calibrate the instru- ment. The count value of this standard must be specified by the treatment supplier. 4.3 Treated Coupon, on which the coating weight is to be determined must be cut to the required size for the instrument from the treated substrate. 4.4 Blank (Bare and Untreated) Coupon should be a sample of the same metal substrate on which the treatment coating weight is to be determined. It may be necessary to prepare a blank coupon from a treated sample if an untreated coupon is not available. To best imitate a bare, untreated blank, abrade a treated coupon that is from the same metal specimen as the test specimen using a small abrasive pad.4 4.4.1 The first abrading is made parallel with the rolling direction of the metal, the second abrading is made perpen- dicular to the rolling direction of the metal, and the third abrading is made parallel with the rolling direction of the metal. This procedure should be repeated until constant read- ings are obtained. Always use the same side of the metal substrate from which the readings of the treated coupon will be taken. 5. Test Specimens 5.1 All test specimens must be flat in the area of measure- ment and free of burrs and distortions that would prevent proper seating in the specimen holder. 5.2 The treatment on the substrate must be uniform in the area of measurement. 5.3 The area of measurement must be maintained free of foreign materials. The specimen must be handled only by the edges that are outside of the area to be measured. 5.4 The coated area of the specimen must be larger than the measuring area. 6. Procedure 6.1 Operate the instrument in accordance with the manufac- turer’s instructions. 6.2 Set the instrument settings as follows: Dial and arm titanium position Seconds indicator pretreatment supplier Multiplier switch pretreatment supplier Response switch pretreatment supplier Range pretreatment supplier Milliamps adjust for calibration of output pretreatment supplier 6.3 All specimens must be seated firmly and securely over the measuring opening. The distance between the measuring apparatus and specimen must be maintained the same as that during the calibration. The blank and treated specimens must be placed in the holder so that the rolling direction of the metal is in the same orientation. Whenever a sample tray holder is a part of the apparatus, the same opening of the slide must be used for the blank and treated specimen unless the openings have been determined to produce equivalent results. If it is necessary to use a backer to hold the test specimen firmly against the window, make sure that the backer is of untreated coupons of the same metal as the specimen. The same backer must be used for each set of measurements. 6.4 Insert the titanium calibration standard that has been recommended by the treatment supplier into the instrument, and obtain a count. Adjust the current with the control knob on the probe until the count value is within 60.50 % of the counts provided by the treatment supplier with each titanium calibra- tion standard. 6.5 Obtain the counts of a blank. 6.6 Obtain the counts of the treated specimen. 6.7 Consult the instrument manufacturer’s instruction manuals for calibrating and operating procedures if the X-ray apparatus has a data handling system for direct readout of coating weights. 7. Calculation 7.1 Use 7.2-7.5 for calculating the coating weight if an automated data handling system is not available. 7.2 The average of a minimum of three readings of both the blank and treated specimen is used to calculate the coating weight. 7.3 Calculate the delta (D) counts by subtracting the counts of the blank from the counts of the treated specimen. 7.4 The coating weight is calculated by dividing the D counts by the conversion factor that is supplied by the treatment supplier for the particular substrate and treatment combination under study. Coating weight ~weight/unit area! 5 D counts conversion factor (1) Other methods as recommended by the treatment supplier may 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 procedure recommended by the treatment supplier. 8. Precision and Bias 8.1 The precision and bias of this test method is being determined and will be available on or before June 2008. 2 A measuring instrument such as a Portaspect, or equivalent, available from Cianflone Scientific, 228 RIDC Park West Drive, Pittsburgh, PA 15275, has been found suitable for this purpose. 3 The calibration standard may be a coupon of titanium base metal or other titanium standard provided by the treatment supplier, or other titanium calibration standard as agreed upon between the purchaser and the seller. A calibration standard such as Brammer BS-T-22, Titanium Standard available from Brammer Standard Company, Inc. 14603 Benfer Road, Houston TX 77069, or equivalent, has been found suitable for this purpose. 4 An abrasive pad such as Scotchbritey No. 7447 General Purpose Hand Pad or No. 96 General Purpose Commercial Scouring Pad, available from 3M, St. Paul, Minnesota, or equivalent, has been found suitable for this purpose. D 6906 – 03 2 9. Keywords 9.1 coating weight; non-chrome; titanium; treatment; X-ray fluorescence ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, are entirely their own responsibility. This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years and if not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standards and should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of the responsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you should make your views known to the ASTM Committee on Standards, at the address shown below. This standard is copyrighted 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 above address or at 610-832-9585 (phone), 610-832-9555 (fax), or service@astm.org (e-mail); or through the ASTM website (www.astm.org). D 6906 – 03 3 主营业务范围：ASTMASTMASTMASTM、NASNASNASNAS、NASMNASMNASMNASM、MILMILMILMIL、ISOISOISOISO、ENENENEN、 DINDINDINDIN、JISJISJISJIS等技术 标准 excel标准偏差excel标准偏差函数exl标准差函数国标检验抽样标准表免费下载红头文件格式标准下载 翻译；技术资料翻译；NADCAPNADCAPNADCAPNADCAP认证 标准资料翻译；国外技术标准中文版优惠低价代购等。 业务 QQQQQQQQ：2298175560229817556022981755602298175560 专业 专注于技术翻译 诚信 实惠 物超所值的服务可靠的质量保证