CN115420570A - Standard substance for zinc alloy spectrum and chemical analysis and preparation method thereof - Google Patents

Abstract

The invention relates to a standard substance for zinc alloy spectrum and chemical analysis, which comprises the following components in percentage by weight: the components and contents of the elements are as follows: al:3.5% -10%; cu:0.20 to 2.8 percent; pb:0.001% -0.025%; sn:0.0001 to 0.003 percent; cd:0.0001 to 0.0005 percent; fe:0.001 to 0.005 percent; mg:0.005% -0.05%; mn:0.001 to 0.01 percent; cr:0.0001 to 0.001 percent; ni:0.0001 to 0.01 percent; si:0.001% -0.02%; the balance of Zn. The standard substance for zinc alloy spectrum and chemical analysis has the advantages of wide component coverage range and reasonable formula setting, and can effectively avoid the problems of easy segregation and poor uniformity caused by unreasonable formula design and content setting.

Description

Standard substance for zinc alloy spectrum and chemical analysis and preparation method thereof

Technical Field

The invention relates to the field of standard substances, in particular to a standard substance for zinc alloy spectrum and chemical analysis and a preparation method thereof.

Background

The zinc alloy is an alloy formed by adding other metal elements on the basis of zinc. The zinc alloy has high relative specific gravity, low melting point, good casting performance and easy die-casting formation, and is melted at 385 ℃; good fluidity, easy fusion welding, brazing and plastic processing; corrosion resistance in the atmosphere; surface treatment may be performed: such as plating, spraying, painting, polishing, grinding, etc. The zinc alloy is widely applied to the fields of mechanical casting and decorative materials, such as die-casting instruments, automobile part shells, furniture fittings, architectural decorations, bathroom fittings, lamp decoration parts, toys, tie clips, belt buckles, various metal decorative buckles and the like.

The standard substance is a means for transferring the quantity value and realizing accurate and consistent measurement, is an indispensable standard for calibrating an analytical instrument, evaluating an analytical method and ensuring the product quality, and has wide application in the departments of industrial production, commercial trade, environmental protection, medical health, scientific research and the like. However, the grades of the cast zinc alloy materials are increasing, and the number of the standard substances suitable for the grades is small, so that the chemical components of the zinc alloy materials cannot be controlled. On the other hand, the existing zinc alloy composition analysis standard substance mainly has the following defects:

(1) The domestic standard substance does not contain Mn, cr, ni, si and other elements, and the content of Al is low, so that the requirements of metering analysis and chemical component control of most zinc alloy materials cannot be met;

(2) The chemical components are important technical indexes of standard substances, a reasonable and feasible chemical component proportioning scheme is designed, and the uniformity and the practicability of the zinc alloy standard substances are directly related; the existing zinc alloy standard substance contains various elements with different contents, and some elements which are easy to segregate and unstable exist in various element components; therefore, how to set the coverage range of the main elements and the content range of each element in the zinc alloy composition analysis standard substance to avoid the problem that the uniformity is poor due to easy segregation of characteristic elements is still a technical difficulty;

(3) Uniformity, stability and accuracy are also important quality indexes of the standard substance; in the preparation process of the zinc alloy component analysis standard substance, how to fully fuse metal materials in all proportions and ensure the uniformity of chemical component distribution in the standard substance and the accuracy of chemical components of the standard substance; currently, there is no good solution.

Disclosure of Invention

The invention aims to provide a standard substance for zinc alloy spectrum and chemical analysis, which has the advantages of wide chemical component coverage range, reasonable element content range, good uniformity, high accuracy and high stability, and a preparation method thereof.

The technical scheme adopted by the invention for solving the technical problems is as follows: a standard substance for zinc alloy spectrum and chemical analysis, wherein: the components and contents of the elements are as follows:

al:3.5% -10%; cu:0.20 to 2.8 percent; pb:0.001% -0.025%; sn:0.0001 to 0.003 percent; cd:0.0001 to 0.0005 percent; fe:0.001 to 0.005 percent; mg:0.005% -0.05%; mn:0.001% -0.01%; cr:0.0001 to 0.01 percent; ni:0.0001 to 0.01 percent; si:0.001% -0.02%; the balance of Zn.

As one of the schemes, the standard substance comprises: the components and contents of the elements are as follows: al:3.95 plus or minus 0.04 percent; cu:0.226 plus or minus 0.004%; pb:0.0029 +/-0.0003%; sn:0.00018 plus or minus 0.00007%; cd:0.00012 plus or minus 0.00004%; fe:0.0015 plus or minus 0.0003%; mg:0.0080 +/-0.0004%; mn:0.0013 plus or minus 0.0002%; cr: less than 0.0002%; ni:0.0003 plus or minus 0.0001%; si:0.0013 plus or minus 0.0004%; the balance of Zn.

As one of the schemes, the standard substance comprises: the components and contents of the elements are as follows: al:9.41 plus or minus 0.05 percent; cu:2.44 plus or minus 0.04 percent; pb:0.015 plus or minus 0.002%; sn:0.0018 plus or minus 0.0003%; cd:0.00027 plus or minus 0.00005%; fe:0.0036 plus or minus 0.0004%; mg:0.044 +/-0.004%; mn:0.0051 + -0.0004%; cr:0.0006 plus or minus 0.0001%; ni:0.0061 plus or minus 0.0004%; si:0.012 plus or minus 0.002%; the balance of Zn.

The invention also provides a preparation method of the standard substance for zinc alloy spectrum and chemical analysis, which comprises the following steps:

s1, material preparation: the chemical composition setting scheme of the standard substance according to any one of claims 1 to 3, wherein various materials are calculated and prepared: comprises pure zinc ingot and other intermediate alloy;

s2, according to the formula setting in the step S1, adding other metal intermediate alloys in a batch and stage mode by taking a pure zinc ingot as a matrix, smelting by adopting a medium-frequency induction furnace, refining by using a refining agent and fully stirring; wherein: controlling the temperature at 650 ℃, performing release casting at a casting speed of 70-80 mm/min, and cooling the water pressure: 0.06 to 0.08MPa;

s3, rapidly cooling the alloy liquid in the step S2 through a circular water hole double-row cooling water jet crystallizer in a direct water-cooling semi-continuous casting mode, casting the alloy liquid into a phi 120mm multiplied by 2000mm round bar and performing ingot casting primary inspection;

s4, placing the ingots qualified in the step S3 in a soaking furnace for homogenization treatment, keeping the temperature of the soaking furnace at 450 +/-5 ℃ for 7 hours, cooling the ingots to normal temperature by water, and then cooling the ingots by air;

s5, (a): peeling the homogenized zinc alloy cast ingot by using a lathe, and extruding the peeled zinc alloy cast ingot into a long rod with the diameter of 40mm multiplied by 5000mm by using a 2000t oil press; removing the head and the tail of the extruded round bar by about 200-500 mm respectively, and processing the round bar into spectral blocks with designed specifications to obtain blocky zinc alloy spectral analysis standard substances;

(b) The method comprises the following steps Peeling the homogenized zinc alloy cast ingot by a lathe for 3-5 mm, and extruding into a round bar; peeling the extruded round bar by a lathe for 3-5 mm, and turning the round bar into scraps by a multi-tooth cutter at the speed of 12-18 r/min to obtain a zinc alloy chemical analysis standard substance;

and S6, respectively carrying out uniformity inspection, stability inspection, fixed value analysis and uncertainty evaluation on the zinc alloy spectral analysis standard substance and the zinc alloy chemical analysis standard substance prepared in the step S5, and then packaging to obtain a finished product.

Preferably, in the step S1, during the material preparation, the components of the raw material pure zinc ingot and the rest of the intermediate alloy need to be re-checked respectively to ensure the accurate smelting components; if the metal surface is covered with oxides, pretreatment is needed to remove the oxides.

Preferably, in step S2: during smelting, inert gas is adopted for protection, so that partial elements are prevented from being oxidized during high-temperature smelting, and the applicability of smelting components and the qualification rate of internal samples are further ensured.

Compared with the prior art, the invention has the following advantages and effects:

1. in the standard substance for zinc alloy spectrum and chemical analysis, the main effective alloy elements are as follows: al, cu, mg; the impurity elements are: pb, sn, cd, fe, mn, cr, ni and Si; compared with the existing zinc alloy composition analysis standard substance, the zinc alloy composition analysis standard substance has wide composition coverage range, can be suitable for controlling the chemical composition of the zinc alloy material, and can also be suitable for the requirements of a photoelectric emission spectrometer, an X-ray fluorescence spectrometer and an inductively coupled plasma emission spectrometer on the zinc alloy standard substance; further, the invention reasonably designs and calculates the contents of Al, cu, mg, pb, sn, cd, fe, cr, mn, ni and Si, and the contents are limited as follows: al:3.5% -10%; cu:0.20 to 2.8 percent; pb:0.001% -0.025%; sn:0.0001 to 0.003 percent; cd:0.0001 to 0.0005 percent; fe:0.001 to 0.005 percent; mg:0.005% -0.05%; mn:0.001% -0.01%; cr:0.0001 to 0.0 percent; ni:0.0001 to 0.01 percent; si:0.001% -0.02%, the problems of easy segregation and poor uniformity caused by unreasonable setting of the content of the characteristic elements can be effectively avoided.

2. In the preparation method of the zinc alloy component analysis standard substance, pure zinc ingots and other intermediate alloys are used as raw materials, all the raw material components are rechecked before smelting and the raw materials with surfaces covered with oxides are pretreated in order to ensure the accuracy of smelting components; in order to ensure the uniformity of the distribution of smelting components, in the smelting process, according to the content requirements of different components and the characteristics of metal elements, the materials are fed in batches and in stages, and after the materials are fed, the materials are fully and mechanically stirred; in order to ensure the stability of the distribution of smelting components, the charging and smelting are carried out under the charging condition selected by the easily-oxidizable elements or under the protection of inert gas; the standard substance prepared by the preparation method has the advantages of good uniformity, high stability and high accuracy after the initial inspection of materials and the inspection of uniformity and stability of chemical components, the chemical components in the standard substance are uniformly distributed, the fixed value data of each element is reliable, and the uncertainty is moderate, so that the standard substance can be used for conventional chemical analysis of zinc alloy and instrument analysis of trace elements.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic diagram of primary uniformity inspection sampling of a zinc alloy ingot in example 2 of the present invention.

FIG. 2 is a schematic diagram of spectrum dotting of a zinc alloy ingot sample in example 2 of the present invention.

Detailed Description

The present invention will be described in further detail with reference to examples, which are illustrative of the present invention and are not to be construed as being limited thereto.

Example 1:

generally, the zinc alloy composition analysis standard substance is composed of a plurality of elements with different contents, and some elements which are easy to segregate and unstable exist in the plurality of element compositions; therefore, the reasonable setting of the chemical components and the content in the standard substance is a necessary premise for realizing the uniformity of the standard substance.

This example provides a standard material for zinc alloy spectrum and chemical analysis, wherein the composition and content range of each element in the standard material are as follows (as shown in table 1).

TABLE 1 Zinc alloy Spectrum and Standard substance composition set Range for chemical analysis (%)

In the standard substance for zinc alloy spectrum and chemical analysis described in this embodiment, a pure zinc ingot is used as a matrix, and the design of the main additive alloy elements is as follows: al, cu, mg, mn, pb, sn, cd, fe, cr, ni and Si; in order to avoid the situation of segregation and instability of elements, the content range of each element is set as follows through proportion calculation: al:3.5% -10%; cu:0.20 to 2.8 percent; pb:0.001% -0.025%; sn:0.0001 to 0.003 percent; cd:0.0001 to 0.0005 percent; fe:0.001 to 0.005 percent; mg:0.005% -0.05%; mn:0.001% -0.01%; cr:0.0001 to 0.001 percent; ni:0.0001 to 0.01 percent; si:0.001% -0.02%; the target standard substance within the setting range has the best uniformity and stability, and specific verification can be seen in the following uniformity and stability analysis data.

Further, the present embodiment specifically provides the following two standard substances for zinc alloy spectrum and chemical analysis, wherein: the composition and mass percentage of each element are shown in table 2.

TABLE 2 Properties and uncertainties (%)

Example 2: a method for preparing the standard substance for the zinc alloy spectrum and chemical analysis in the embodiment 1 specifically comprises the following steps:

s1, material preparation:

according to the chemical composition set-up protocol of the two standard substances described in table 2 of example 1, the respective materials were calculated and prepared separately: comprises pure zinc ingot and other intermediate alloy;

wherein: before material preparation, components of the raw material pure zinc ingot and other intermediate alloys need to be rechecked respectively to ensure accurate smelting components; if the metal surface is covered with oxides, pretreatment is needed to remove the oxides so as to ensure the accuracy of the chemical components of the standard substances during smelting;

s2, according to the formula setting in the step S1, adding other metal intermediate alloys in a batch and stage mode by taking a pure zinc ingot as a matrix, smelting by adopting a 250kg medium frequency induction furnace, refining by using a refining agent and fully stirring to ensure the uniformity of chemical component distribution;

wherein: controlling the casting temperature at 650 ℃, performing release casting at the casting speed of 70-80 mm/min and the cooling water pressure of 0.06-0.08 MPa; in the smelting process, a photoelectric emission spectrometer and an inductively coupled plasma atomic emission spectrometer are used for carrying out real-time analysis, inspection and control;

s3, rapidly cooling the alloy liquid in the step S2 through a circular water hole double-row cooling water jet crystallizer in a direct water-cooling semi-continuous casting mode, casting the alloy liquid into a phi 120mm multiplied by 2000mm round bar, and performing ingot casting uniformity segregation initial detection, wherein the data are shown in a table 3;

s4, placing the ingots qualified in the step S3 in a soaking furnace for homogenization treatment, keeping the temperature of the soaking furnace at 450 +/-5 ℃ for 7 hours, cooling the ingots to normal temperature by water, and then cooling the ingots by air;

s5, (a): peeling the homogenized zinc alloy cast ingot by a lathe for 3-5 mm, and extruding the zinc alloy cast ingot on a 2000t oil press to form a long rod with the diameter of 40mm multiplied by 5000 mm; removing the head and the tail of the extruded round rod by about 200-500 mm respectively, processing into small cylinders with the designed specification (phi 40 multiplied by 30 mm), numbering, and turning flat end surfaces to prepare the massive spectral analysis standard substance; the serial numbers of the two zinc alloy spectral analysis standard substances are ZBY and ZBY937 respectively;

(b) Peeling the homogenized zinc alloy cast ingot by a lathe for 3-5 mm, and extruding the zinc alloy cast ingot into a long rod with the diameter of 40mm on a 2000t oil press; peeling the extruded round bar by a lathe for 3-5 mm, turning the round bar into chips by a multi-tooth cutter at the speed of 12-18 r/min, and processing the chips into 0.84-0.18 mm chips after passing through a sieve to obtain zinc alloy chemical analysis standard substances with the numbers of ZBY9361 and ZBY9371 respectively;

and S6, respectively carrying out uniformity inspection, stability inspection, fixed value analysis and uncertainty evaluation on the zinc alloy spectral analysis standard substance and the zinc alloy chemical analysis standard substance prepared in the step S5, and then packaging to obtain a finished product.

As a preferred embodiment, in step S2 of this embodiment: during smelting, inert gas is adopted for protection, so that partial elements are prevented from being oxidized during high-temperature smelting, and the applicability of smelting components and the qualification rate of internal samples are further ensured.

The uniformity, stability and accuracy of chemical components of the prepared zinc alloy spectrum and chemical analysis standard substance in the embodiment are verified from four aspects;

1. primary detection of uniformity:

(a) Zinc alloy spectral analysis standard substance

As shown in fig. 1, the round bar material prepared according to the step S3 is obtained by taking a sample with a height of 10mm from a position (a) about 200mm away from the head of the bar, a position (b) in the middle of the bar and a position (c) about 200mm away from the tail of the bar, and performing spectrometry on a spectrometer by using a special standard substance for the spectrometer as a tracing, using an imported zinc alloy standard substance for complete standardization, and then using a standard substance with the same content and the same mark as the imported zinc alloy standard substance for type standardization;

as shown in fig. 2, five diameter-parallel determinations were made on each side as shown in the spectral dotting diagram, and the radial segregation test for uniformity was performed by the range method; the radial segregation test data is shown in table 3.

TABLE 3 radial head-to-tail segregation test for zinc alloy spectral analysis standard (%)

As can be seen from Table 3, the extreme differences of the heads, the middles and the tails of the zinc alloy spectral analysis standard substances are smaller than the repeatability r in the national standard GB/T26042-2010 photoelectric emission spectrometry for the zinc and zinc alloy analysis methods, and the cast ingots are qualified in initial inspection.

(b) A zinc alloy chemical analysis standard substance;

packaging the processed and uniformly mixed chemical chip samples into bottles, sequentially discharging the chemical chip samples, randomly selecting 12 bottles at different numbers, and detecting according to GB/T12689.12-2004 inductively coupled plasma-emission spectrometry for measuring the amounts of lead, cadmium, iron, copper, tin, aluminum, arsenic, antimony, magnesium, lanthanum and cerium in the chemical analysis method for zinc and zinc alloys, wherein the detection data are shown in Table 4.

Table 4 initial homogeneity test (%)

TABLE 4

Wherein: according to the table 4, the extreme difference of the primary uniformity test of the zinc alloy chemical analysis standard substance is smaller than the repeatability r of the ICP-AES method specified in the national standard GB/T12689.12-2004, and the primary uniformity test of the chemical analysis standard substance is qualified.

(II) uniformity test

(a) Zinc alloy spectral analysis standard substance

According to the requirements of the technical specification of standard substances, 2-3 samples (phi 40 multiplied by 30 mm) are respectively cut from the head, the middle and the tail of all finished slender rods, 20 samples are counted in sequence, and the uniformity recheck is carried out. On a photoelectric emission spectrometer, a special standard substance prepared by the spectrometer is firstly used for tracing, an imported zinc alloy standard substance is used for complete standardization, standard substances with similar contents and the same brands are used for type standardization, then spectrum measurement is carried out, and uniformity inspection is carried out. The sampling schematic diagram of the spectrum inspection is shown in FIG. 1; counting the test result by a variance method; the statistical results are shown in table 5;

TABLE 5 homogeneity test F-value (F) of standard material for zinc alloy spectral analysis _0.05 ＝1.84)

Sample numbering	Al	Cu	Pb	Sn	Cd	Fe	Mg	Mn	Cr	Ni	Si
												ZBY936	0.81	0.97	0.99	1.12	1.10	0.98	0.94	1.18		1.02	1.02
ZBY937	1.19	1.14	1.15	1.17	1.09	1.14	0.92	1.13	0.99	1.06	0.87

When statistic F<Fα _(0.05) And (3) when the average value of the measured values is larger than the preset value, the data in the group and the data between the groups have no obvious difference, and the uniformity test is qualified.

When statistic F>Fα _(0.05) And if so, the data in the groups and the data between the groups are obviously different, and the uniformity test is unqualified.

Counting that F value of each element is less than F alpha by a variance method _(0.05) And (4) testing the uniformity of the zinc alloy spectral analysis standard substance to be qualified.

(b) Zinc alloy chemical analysis standard substance

According to the requirements of standard substance technical specifications, 20 bottles of samples are randomly selected from the packaged samples and are numbered in sequence, uniformity inspection is carried out by using an inductive coupling plasma emission spectrometry, high-purity zinc and standard solution are used as working curves, and quality monitoring is carried out on approved and released national first-class standard substances with similar contents. The method and the minimum sample weighing amount used in each chemical analysis are shown in table 6, and the test results are counted by a variance method; the statistical results are shown in Table 6-1;

TABLE 6 Standard substance homogeneity test analysis method and minimum sample weight for chemical analysis of Zinc alloy

TABLE 6-1 Zinc alloy chemical analysis Standard substance homogeneity test F-value (F) _0.05 ＝1.84)

Sample numbering	Al	Cu	Pb	Sn	Cd	Fe	Mg	Mn	Cr	Ni	Si
												ZBY9361	0.87	1.15	0.87	0.88	0.91	1.14	0.84	0.82		1.12	0.90
ZBY9371	0.83	0.82	1.14	0.92	1.01	0.86	0.85	1.10	0.83	0.84	0.81

When statistic F<Fα _(0.05) And (3) when the average value of the measured values is larger than the preset value, the data in the group and the data between the groups have no obvious difference, and the uniformity test is qualified.

When statistic F>Fα _(0.05) When the data is in the same group, the data in the same group and the data in the same group are different significantlyAnd the uniformity test is unqualified.

Counting that F value of each element is less than F alpha by a variance method _(0.05) And (4) the uniformity of the zinc alloy chemical analysis standard substance is qualified.

(III) stability test

The standard substance is subjected to stability investigation for multiple times within two years, the measured result is subjected to stability statistical test by a straight line fitting method, and if the slope | b ₁ |＜t _α，(n-2) ×s(b ₁ ) The slope is not significant indicating that the sample is stable. In the formula b ₁ To fit the slope of the straight line, s (b) ₁ ) Is the uncertainty of the slope, t _α，(n-2) The student distribution for degree of freedom n-2 and a certain confidence level.

The measured values of 5 stability tests from 2017 to 2019 are calculated (the results are shown in tables 7-1 and 7-2), and the results show that the stability test data are consistent in two years and the stability of the sample is good. And comparing the stability investigation result with the final fixed value uncertainty, wherein the difference values of the two measurements of all the stability investigation items do not exceed the uncertainty of the fixed value, the stability uncertainty obtained by calculation is small, the stability is good, and the validity periods of the zinc alloy spectrum and the chemical analysis standard substance in the embodiment are determined to be at least 15 years by referring to the similar standard substances.

TABLE 7-1 test results of stability of zinc alloy spectral analysis standard (%)

Note: mu.s _t Stability uncertainty.

TABLE 7-1

Note: mu.s _t Stability uncertainty.

TABLE 7-2 evaluation results of stability of standard substances for chemical analysis of Zinc alloy (%)

Note: mu.s _t Stability uncertainty.

TABLE 7-2

Note: mu.s _t Stability uncertainty.

(III) quantitative analysis

In this example, the zinc alloy spectral analysis standard substances with the numbers ZBY, ZBY937 and the zinc alloy chemical analysis standard substances with the numbers ZBY9361, ZBY9371 were subjected to constant value analysis; wherein: in addition to the unit, a plurality of units with certain test levels at home and abroad are invited to participate in fixed value analysis at the same time, one or more accurate and reliable analysis methods are selected for collaborative fixed value analysis, each element (same method) reports four data in the analysis process, the extreme difference of each group of four data is less than the precision of the corresponding analysis method, and the analysis methods adopted by the fixed value units and the fixed values are respectively shown in tables 8 and 9; the approved values and uncertainty data for each element in the standard material, as shown in table 10;

TABLE 8 constant value units and laboratory sequence codes

TABLE 9 analytical methods used for valuing

TABLE 9 continuation

TABLE 9 continuation

Note: the standard solutions in the table are traceability substances, and the other standard substances are quality control samples. Cu with the content of more than 1 percent is measured by an atomic absorption spectrometry method for reducing the sample weighing; measuring <0.0005% of Sn, cd and Ni by an ICP-AES method by increasing sample weighing and a standard addition method; <0.010% Si was determined by molybdenum blue photometry using standard addition methods.

Traceability

(1) The method adopts the cooperative valuing of a plurality of laboratories, and the majority of the valuing units are qualified national approved units or units with experience of developing or measuring standard substances for many years.

(2) The instruments used in each laboratory are calibrated by metering, and the standard substances or standard solutions are standard substances with confirmed purity or standard solutions approved and released by the state.

(3) The method adopts a standard method and different principles to accurately and reliably test, si adopts a molybdenum blue photometry and an inductively coupled plasma emission spectrometry, al adopts an EDTA titration method, an inductively coupled plasma emission spectrometry and the like, and the test is carried out by using approved national first-grade standard substances and national approved standard solutions. The reference substances, standard substances or standard solutions used are shown in Table 10.

TABLE 10 Standard substance/Standard solution for determination of Zinc alloy Spectroscopy and Standard substance for chemical analysis

And (3) summarizing and processing analysis data: in the standard substance obtained by analysis of each cooperative unit, each element (same method) reports four data, the extreme difference of the data is checked whether an abnormal value exists in the group according to the repeatability r of the method in the national standard, and then the average value of the data is calculated. And (5) checking whether the results of each group are equal in precision by using a Koclen criterion, and determining that the results are qualified. Whether the average values accord with normal distribution or not is examined by a Charperot-Wilk method, and the conclusion is qualified. And (5) checking whether each average value has an abnormal value by using a Grabbs method, and concluding that the average value is qualified. When each group of data has no abnormal value, calculating the arithmetic mean value and the standard deviation of each group of data, and amending the effective digits of the standard value according to the method precision and GB/T8170-2008, wherein the standard deviation is amended according to the principle of only leaving nothing, and the digits of the standard deviation and the standard value are aligned; specific fixed value data and calculated uncertainty are shown in tables 11-1 and 11-2.

TABLE 11-1 approved values and uncertainties (%)

TABLE 11-2 approved values and uncertainties (%)

As can be seen from tables 8 to 11-1 and 11-2, in the present application, in the process of quantitative analysis of standard substances, one or more analysis methods that are fully verified by national standards or technical standards are preferably used for determining parameters of each item, and all the invited laboratories have many years of experience with zinc alloy standard substances or pass laboratory approval or measurement certification. In the analysis and determination process, a mode that a reference substance and a standard solution are used as working curves is adopted, the issued national first-class standard substance is used for quality monitoring, the determination result is compared with the standard value of the standard substance, and the reliability of the analysis method is indirectly verified.

Further, the reliability of the fixed value data and the fixed value analysis method is verified by comparing the data with similar standard substances at home and abroad, the comparison data is shown in table 12, and specific comparison objects are as follows: the national institute of standards NIST Standard substance systems include zinc alloy spectra and chemical standards (numbered SRM627, SRM630 and SRM94 c), and the British MBH company includes spectra and chemical standards (numbered CZ42XZ30 and 43XZ 13). The national defense science and engineering committee primary chemical metering station comprises a zinc alloy spectrum and chemical standard substances GBW02704 and GBW02705-02709. The method comprises the steps of firstly tracing by using a special standard substance for a spectrometer, completely standardizing by using an imported zinc alloy standard substance, and then performing spectral measurement on a national first-class standard substance GBW02705-02709 by using developed zinc alloy standard substances ZBY and ZBY937 for type standardization.

TABLE 12 comparison of spectra and chemical analysis standards of the same type at home and abroad (%)

TABLE 12 continuation

As can be seen from the analysis of tables 11-1, 11-2 and 12, the standard substance selects similar standard substances with similar element contents at home and abroad for comparison tests, and as can be seen from the comparison data, the uncertainty of each element in the series of zinc alloy standard substances is close to the uncertainty of similar standard substances at home and abroad, and the uncertainty of individual element is superior to the uncertainty of similar standard substances at home and abroad, which shows that: the method used for carrying out fixed value analysis on the standard value data of 11 elements such as Al, cu, pb, sn, cd, fe, mg, mn, cr, ni and Si in the embodiment has accurate reliability.

In addition, the zinc alloy spectrum and chemical analysis standard substance prepared by the invention have better chemical composition uniformity and higher stability through quality inspection and data verification, and the standard substance has uniform content of each element, reliable fixed value data and moderate uncertainty, and can meet the requirements of curve establishment and correction detection of a zinc alloy spectrometer, chemical composition control on a zinc alloy material, evaluation on a zinc alloy method, material assignment and the like.

In addition, it should be noted that the shapes, names, and the like of the components of the embodiments described in the present specification may be different. All equivalent or simple changes of the structure, the characteristics and the principle of the invention which are described in the patent conception of the invention are included in the protection scope of the patent of the invention. Various modifications, additions and substitutions for the specific embodiments described may be made by those skilled in the art without departing from the scope of the invention as defined in the accompanying claims.

Claims (6)

1. A standard substance for zinc alloy spectrum and chemical analysis is characterized in that: the composition and content range of each element are as follows:

al:3.5% -10%; cu:0.20 to 2.8 percent; pb:0.001% -0.025%; sn:0.0001 to 0.003 percent; cd:0.0001 to 0.0005 percent; fe:0.001 to 0.005 percent; mg:0.005% -0.05%; mn:0.001% -0.01%; cr:0.0001 to 0.0 percent; ni:0.0001 to 0.01 percent; si:0.001% -0.02%; the balance of Zn.

2. The standard substance for zinc alloy spectral and chemical analysis according to claim 1,

al:3.95 plus or minus 0.04 percent; cu:0.226 +/-0.004%; pb:0.0029 +/-0.0003%; sn:0.00018 plus or minus 0.00007%; cd:0.00012 plus or minus 0.00004%; fe:0.0015 plus or minus 0.0003%; mg:0.0080 +/-0.0004%; mn:0.0013 plus or minus 0.0002%; cr: less than 0.0002%; ni:0.0003 plus or minus 0.0001%; si:0.0013 plus or minus 0.0004%; the balance of Zn.

3. The standard substance for zinc alloy spectral and chemical analysis according to claim 1,

al:9.41 plus or minus 0.05 percent; cu:2.44 plus or minus 0.04 percent; pb:0.015 plus or minus 0.002%; sn:0.0018 plus or minus 0.0003%; cd:0.00027 plus or minus 0.00005%; fe:0.0036 +/-0.0004%; mg:0.044 +/-0.004%; mn:0.0051 plus or minus 0.0004%; cr:0.0006 plus or minus 0.0001%; ni:0.0061 plus or minus 0.0004%; si:0.012 plus or minus 0.002%; the balance of Zn.

4. A preparation method of a standard substance for zinc alloy spectrum and chemical analysis is characterized by comprising the following steps:

s1, material preparation: the chemical composition setting scheme of the standard substance according to any one of claims 1 to 3, wherein various materials are calculated and prepared: comprises pure zinc ingot and other intermediate alloy;

s2, according to the formula setting in the step S1, adding other metal intermediate alloys in a batch and stage mode by taking a pure zinc ingot as a matrix, smelting by adopting a medium-frequency induction furnace, refining by using a refining agent and fully stirring; wherein: controlling the temperature at 650 ℃, performing release casting at a casting speed of 70-80 mm/min, and cooling water pressure: 0.06-0.08 MPa;

s3, rapidly cooling the alloy liquid in the step S2 through a circular water hole double-row cooling water jet crystallizer in a direct water-cooling semi-continuous casting mode, casting the alloy liquid into a phi 120mm multiplied by 2000mm round bar and performing ingot casting primary inspection;

s4, placing the ingots qualified in the step S3 in a soaking furnace for homogenization treatment, keeping the temperature of the soaking furnace at 450 +/-5 ℃ for 7 hours, cooling the ingots to normal temperature by water, and then cooling the ingots by air;

s5, (a): peeling the homogenized zinc alloy cast ingot by using a lathe, and extruding the zinc alloy cast ingot into a long rod with the diameter of 40mm multiplied by 5000mm by using a 2000t oil press after peeling; removing the head and the tail of the extruded round bar by about 200-500 mm respectively, and processing the round bar into spectral blocks with designed specifications to obtain blocky zinc alloy spectral analysis standard substances;

(b) The method comprises the following steps Peeling the homogenized zinc alloy cast ingot by a lathe for 3-5 mm, and extruding into a round bar; peeling the extruded round bar by a lathe for 3-5 mm, and turning the round bar into scraps by a multi-tooth cutter at the speed of 12-18 r/min to obtain a zinc alloy chemical analysis standard substance;

and S6, respectively carrying out uniformity inspection, stability inspection, fixed value analysis and uncertainty evaluation on the zinc alloy spectral analysis standard substance and the zinc alloy chemical analysis standard substance prepared in the step S5, and then packaging to obtain a finished product.

5. The preparation method according to claim 4, wherein in the step S1, the components of the raw material pure zinc ingot and the rest of the intermediate alloy are respectively rechecked to ensure the accurate smelting components when preparing the material; if the metal surface is covered with oxides, pretreatment is needed to remove the oxides.

6. The method according to claim 4, wherein in step S2: and in the smelting process, inert gas is adopted for protection.

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