ASTM B890 - 20

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Designation: B890 −20

Standard Test Method for

Determination of Metallic Constituents of Tungsten Alloys

and Tungsten Hardmetals by X-Ray Fluorescence

Spectrometry

This standard is issued under the ﬁxed designation B890; 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 (´) indicates an editorial change since the last revision or reapproval.

1. Scope

1.1 This test method describes a procedure for the determi-

nation of the concentration, generally reported as mass percent,

of the metallic constituents of tungsten-based alloys and

hardmetals utilizing wavelength dispersive X-ray ﬂuorescence

spectrometry (XRF). This test method incorporates the prepa-

ration of standards using reagent grade metallic oxides,

lithium-borate compounds, and fusion techniques. This test

method details techniques for preparing representative speci-

mens of both powder and sintered tungsten-based material.

This test method is accurate for a wide range of compositions,

and can be used for acceptance of material to grade speciﬁca-

tions.

1.2 This test method is applicable to mixtures of tungsten or

tungsten carbide with additions of refractory metal carbides

and binder metals. Table 1 lists the most common elemental

constituents and their concentration range. Note that many of

these occur as metallic carbides.

1.3 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, health, and environmental practices and deter-

mine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accor-

dance with internationally recognized principles on standard-

ization established in the Decision on Principles for the

Development of International Standards, Guides and Recom-

mendations issued by the World Trade Organization Technical

Barriers to Trade (TBT) Committee.

2. Referenced Documents

2.1 ASTM Standards:

E135 Terminology Relating to Analytical Chemistry for

Metals, Ores, and Related Materials

E1361 Guide for Correction of Interelement Effects in

X-Ray Spectrometric Analysis

3. Terminology

3.1 For deﬁnitions of terms used in this test method, refer to

Terminology E135.

4. Summary of Test Method

4.1 A suite of standards which closely match the chemical

content of the material to be analyzed are prepared using

reagent grade metallic oxides. Test samples are oxidized in a

high-temperature furnace open to air. Fused glass specimens

are prepared for these standards and for the test samples to be

analyzed. These specimens of oxidized tungsten or tungsten

carbide alloys are irradiated with an energetic primary X-ray

beam. The intensity of the resultant secondary X-rays, charac-

teristic in energy, for each elemental constituent is measured by

means of a suitable detector or combination of detectors after

diffraction by a Bragg spectrometer. The concentration of each

constituent element is calculated by comparison with standard

samples which closely match the chemical content of the

analyzed material. The calculation may be manual, incorporate

a calibration curve, or be performed by a computer program

which incorporates correction routines for X-ray absorption

and enhancement effects (see Guide E1361).

5. Signiﬁcance and Use

5.1 This test method allows the determination of the chemi-

cal composition of powdered and sintered tungsten-based

This test method is under the jurisdiction of ASTM Committee B09 on Metal

Powders and Metal Powder Products and is the direct responsibility of Subcom-

mittee B09.06 on Cemented Carbides.

Current edition approved Oct. 1, 2020. Published November 2020. Originally

approved in 1998. Last previous edition approved in 2012 as B890 – 07(2012). DOI:

10.1520/B0890-20.

For referenced ASTM standards, visit the ASTM website, www.astm.org, or

contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM

Standards volume information, refer to the standard’s Document Summary page on

the ASTM website.

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the

Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

hardmetals. This test method is not applicable to material

which will not oxidize readily at high temperatures in air, such

as tungsten/copper, tungsten/silver alloys, or tungsten/cobalt-

ruthenium alloys.

5.2 This test method speciﬁed lithium-borate compounds

for the glass fusion material. However, numerous other choices

are available. These include other lithium-borate compounds,

sodium carbonate and borate mixtures, and others. The meth-

odology speciﬁed here is still applicable as long as the same

fusion mixture is used for both standards and specimens.

6. Interferences

6.1 Errors in XRF-determined compositional values may be

encountered due to X-ray enhancement and absorption effects

dependent on the elements present and the X-ray line being

measured for a speciﬁc element. This effect can be reduced by

determination of correction factors using appropriate standards

and interelement correction routines, manual or computerized.

6.2 Accuracy and precision of the analytical results obtained

from molybdenum-containing samples may be rendered unre-

liable due to the sublimation and evaporation of molybdenum

from the material during the oxidation step in specimen

preparation.

6.3 Incorporation of the fusion method of specimen prepa-

ration will:

6.3.1 Reduce the deleterious inﬂuence of particle size ef-

fects experienced when analyzing powder materials by varying

particle size.

6.3.2 Reduce inhomogenieties within a sample.

6.3.3 Improve penetration of X rays.

6.3.4 Reduce interelement interferences.

7. Apparatus

7.1 X-Ray Fluorescence Wavelength Dispersive Spectrom-

eter.

7.2 Fluxer—An automated high-temperature mixing device

capable of melting, mixing, and pouring a molten liquid

specimen into a proper casting dish, is highly preferred.

7.3 Analytical Balance, readability of 0.0001 g.

7.4 Toploading Balance, readability of 0.001 g.

7.5 Ordinary Laboratory Apparatus.

7.6 One Pt - 5 % Au Casting Dish (minimum).

7.7 One Pt - 5 % Au Crucible (minimum).

7.8 Platinum Tipped Tongs.

7.9 Weighing Paper.

7.10 Chemical Spoon and Scoopula.

7.11 Ceramic or Quartz Combustion Boat.

7.12 High Temperature Tube or Muffle Furnace, open to the

atmosphere.

7.13 Self-adhering Stickers,

⁄

by 1 in.

7.14 Ceramic Mortar and Pestle.

7.15 Tungsten Carbide Mortar and Pestle.

7.16 Miniature Mixer, optional.

8. Reagents and Materials

8.1 Purity of Reagents—Reagent grade chemicals shall be

used in all tests. Unless otherwise indicated, it is intended that

all reagents conform to the speciﬁcation of the Committee on

Analytical Reagents of the American Chemical Society where

such speciﬁcations are available.

Other grades may be used,

provided it is ﬁrst ascertained that the reagent is of sufficiently

high purity to permit its use without lessening the accuracy of

the determination.

8.2 Di-lithiumtetraborate (Li

):Lithiummetaborate

(LiBO

), 66 + 34 by mass percentage.

8.3 Lithium Bromide (LiBr).

8.4 Metallic Oxide Powder, highest oxidation state for

elements of interest; that is Co

,Cr

,Fe

, HfO

MoO

,Nb

, NiO, Ta

,TiO

, and WO

Warning—Several of the metallic oxides used in this test

method are highly toxic and possibly carcinogenic, such as

, NiO, or V

. Extreme care should be used at all times

when handling this material (especially V

). All mixing of

standards should be performed in a fume hood. All of the

lithium compounds are water-soluble and therefore able to be

absorbed into the body by inhalation and possibly by absorp-

tion through the skin. This material should be weighed in a

fume hood.

8.5 Citric Acid (HO·C(COOH)(CH

·COOH)

, used for

cleaning purposes only.

9. Specimen Preparation

9.1 Prepare specimens of the material to be analyzed by

oxidizing, weighing, and fusing samples.

9.2 Place 3 to5gofpowdered specimen in a labeled

ceramic combustion boat. If a sintered sample is to be

analyzed, then the sample must be crushed or pulverized into

small pieces or chips must be produced by machining prior to

placement in the combustion boat. To crush or pulverize a

sample, a tungsten carbide mortar and pestle should be used to

reduce the incidence of contamination.

Reagent Chemicals, American Chemical Society Speciﬁcation, American

Chemical Society, Washington, DC. For suggestions on the testing of reagents not

listed by the American Chemical Society, see Analar Standards for Laboratory

Chemicals, BDH Ltd,. Poole, Dorset, U.K., and the United States Pharmacopeia

and National Formulatory, U.S. Pharmaceutical Convention, Inc. (USPC),

Rockvale, MD.

TABLE 1 Elemental Constituents and Concentration Range

Element Concentration, Mass %

(minimum - maximum)

Chromium (Cr) 0.05 - 5.0

Cobalt (Co) 0.05 - 40

Hafnium (Hf) 0.05 - 2.0

Iron (Fe) 0.05 - 2.0

Molybdenum (Mo) 0.05 - 5.0

Nickel (Ni) 0.05 - 30

Niobium (Nb) 0.05 - 15

Tantalum (Ta) 0.05 - 30

Titanium (Ti) 0.05 - 30

Vanadium (V) 0.05 - 2.0

B890 − 20

9.3 Oxidize the specimen in the heat zone of a high-

temperature tube or muffle furnace open to the atmosphere at

825 625 °C. All specimens must be fully oxidized.

9.4 When the specimen has been completely oxidized (4 to

6 h), remove from the furnace and allow to cool.

NOTE 1—Complete oxidation of a sintered magnetic tungsten hard

metal sample can be checked by testing the cool oxidized chips with a

magnet. If any of the sample is still magnetic, recrush the sample and

place back in the furnace for further oxidation.

9.5 Pour the specimen onto a clean sheet of paper or into a

clean mortar and gently crush with a pestle.

9.6 Transfer the specimen to a labeled specimen vial.

9.7 Prepare a fusion mixture to be used with the oxidized

samples. For example, a mixture of dilithium tetraborate:

lithium metaborate with a 0.2 g addition of lithium bromide

can be used. The mixture should be used the day it is made.

Unused portions can be stored in an air tight container or

dessicator.

NOTE 2—Other fusion materials can be used. See 5.2.

9.8 In a fume hood, transfer the fusion mixture to a platinum

crucible immediately prior to weighing of the oxidized sample

material.

9.9 Weigh out 1.0000 60.0005 g of oxidized specimen and

transfer to the platinum crucible. Mix gently with the fusion

mixture.

NOTE 3—If there is not enough sample to make a standard fusion, or the

amount of the total mixture is too large for the casting dish, proportionate

amounts of oxidized test sample and fusion mixture can be utilized to

prepare a specimen recognizing that larger fractional errors may be

incurred in the analysis. This should only be used when absolutely

necessary.

9.10 Using the ﬂuxer, melt the specimen at the lowest

temperature required for dissolution of the sample by the

fusion mixture used and cast into a heated platinum casting

dish.

9.10.1 Warning—The process of making glass fusions

exposes personnel to high-temperature liquids. Extreme care

should be exercised while preparing these samples. These high

temperatures also cause some volatilization of the lithium

compounds. The ﬂuxer should have an exhaust hood to remove

these gases from the facility. The lithium compounds used in

this procedure are hygroscopic. Material open to the atmo-

sphere for an extended period of time will absorb moisture.

Exposure of this material to subsequent high heat will cause

rapid formation of steam and may cause spattering of the

molten glass onto the instrument and possibly the operator.

9.11 While the fused specimen is cooling, remove the

crucible from the instrument with the platinum-tipped tongs

and cool.

9.12 Place the crucible in a 1000 mL beaker which has a

2-volume percent solution of citric acid. Put the beaker on a hot

plate and warm the solution. The crucible should be clean in

approximately 30 min. Remove the crucible from the acid bath

with tongs and rinse with water. Dry the crucible and store.

9.13 When the fused specimen is cool, remove from the

casting dish by gripping the dish ﬁrmly with tongs, turning the

dish over, and gently tapping against a clean paper. The dish

and fused specimen should cleanly separate. Label the fused

specimen with a self-adhering tag.

NOTE 4—Any evidence of wetting between the specimen and the

platinum crucible or casting dish is an indication that the specimen has

reacted with these vessels and is not a valid representative sample.

9.14 If the fusion crystallizes (cooling slowly) or fractures

(cooling fast), crush the fusion and recast. If the fused

specimen cannot be removed from the platinum casting dish

with very light tapping, dissolve the specimen from the dish

using a warm 2-volume percent citric acid solution. Prepare a

new specimen in accordance with 9.7 – 9.10.

Caution—Excessive prying or tapping of the crystallized

specimen while it is in the dish will damage the platinum ware.

10. Standardization of Spectrometer and Analysis

10.1 Based on the X-ray spectrometer conﬁguration and

instrument manufacturer’s operating instructions, determine

the instrument operating parameters to provide optimum spec-

tral analysis for each element being analyzed in a given matrix.

Table 2 provides the approximate X-ray peak positions (Bragg

angle - 2Θ) and crystals typically used for each of the elements

of interest.

10.2 If required, normalize the X-ray spectrometer operat-

ing parameters to obtain the appropriate secondary X-ray

intensities from the reference standards utilized.

10.3 Measure X-ray intensities on a sufficient number of

fused standards to establish a calibration curve (intensity

versus concentration of analyte) for each element of interest.

NOTE 5—The number of standards sufficient to establish a calibration

curve is dependent on the range of concentrations to be analyzed for each

element. In all cases, a minimum of six standards is required.

10.4 Calibration curves may be established manually, or

corrections for interelement effects may be calculated using

XRF vendor-supplied computer software.

NOTE 6—Accuracy of a given interelement correction routine can be

veriﬁed by including one or more reference standards as “blind” un-

knowns as part of an analysis.

11. Procedure

11.1 Obtain X-ray intensity data from the fused test speci-

mens.

TABLE 2 Analytical X-ray Lines

Element

Symbol

Shell

Series

Reﬂection

Order

Bragg

Angle 2Θ

Wavelength,

Crystal

Co Kα1 52.788 1.7906 LiF100

Cr Kα1 69.368 2.2913 LiF100

Fe Kα1 57.526 1.9376 LiF100

Hf Lα1 45.880 1.5690 LiF100

Mo Kα1 20.276 0.7092 LiF100

Nb Kα1 21.340 0.7461 LiF100

Ni Kα1 48.632 1.6594 LiF100

Ta Lα1 64.640 1.5222 LiF110

Ti Kα1 86.186 2.7502 LiF100

VKα1 123.172 2.5054 LiF110

B890 − 20

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摘要：

ASTM B890 - 20 是一项由美国材料与试验协会（ASTM）发布的国际标准，全称为《金属粉末及其制品中表观密度与振实密度测定的标准试验方法》。该标准主要适用于金属粉末、合金粉末以及相关粉末冶金制品的密度测量，通过规范化的漏斗法和振实法，确保测试结果具有可重复性和比较性。内容涵盖试验设备要求、操作步骤、样品处理、结果计算及报告格式，涉及粉末流动性与堆积特性的评估，广泛应用于粉末冶金、增材制造、电子材料、硬质合金等领域。更新至2020年版本后，标准在环境条件控制、仪器校准及数据处理精度方面进

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