CN104458802A - Method for measuring nitrogen content of rare earth permanent magnetic material neodymium-iron-boron alloy by using thermal conductivity method - Google Patents

Abstract

The invention relates to a method for measuring the nitrogen content of a rare earth permanent magnetic material neodymium-iron-boron alloy by using a thermal conductivity method. The method comprises the following steps: putting a nickel bag containing graphite powder into an oxygen-nitrogen tester to measure peak and nitrogen results of nitrogen in the nickel bag; then putting a standard sample into the nickel bag, and compacting a seal of the nickel bag by using a wire stripper to measure the peak and nitrogen results of nitrogen; continuously measuring the standard sample for more than three times according to the method to obtain different measured values; clicking a calibration button of nitrogen in an instrument calibration page to ensure that an instrument performs calibration automatically and then a new calibration factor appears, and clicking a saving button to enter the next step; weighing a to-be-measured sample, putting the sample into the nickel bag, and compacting the seal of the nickel bag by using the wire stripper to measure the peak and nitrogen results of nitrogen, thereby obtaining an analysis result of nitrogen. Therefore, the accuracy is measured by comparing with the measurement of the standard sample.

Description

A kind of method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys

Technical field

The present invention relates to rare earth material analysis field, particularly relate to a kind of method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys.

Background technology

China relies on rare earth resources advantage and production cost advantage, greatly develops neodymium iron boron magnetic body industry, has become the first in the world big producing country and consumption big country.Due to characteristic and the more traditional magnetic material excellence of cost performance of neodymium iron boron magnetic body, all trades and professions such as computing machine, motor, aerogenerator, electric automobile, instrument and meter, nuclear resounce imager and space flight and aviation omniselector are widely used in.At emerging technology areas such as magnetic suspension trains, there is huge potential application foreground.

The GN 2 content is one of leading indicator of Nd-Fe-Bo permanent magnet material quality, and the Accurate Determining therefore carrying out the GN 2 in Nd-Fe-Bo permanent magnet material is significant.The content method of mensurated gas composition nitrogen has inert gas fusion method and chemical method two kinds, compared to chemical method, and the features such as fusion method has good stability, and precision is high, quick.Be applicable to accurate, the Fast Measurement of the GN 2 in Nd-Fe-Bo permanent magnet material.

Summary of the invention

The technical problem to be solved in the present invention is to provide that a kind of operating process is short, and cost is low, and fast, efficient, accurately, good stability, is easy to the method for nitrogen content in the mensuration rare earth permanent-magnetic material Nd Fe B alloys grasped.To solve the problem of mensuration without standard test of nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys.

For reaching above-mentioned purpose, a kind of method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys of the present invention, comprises the following steps:

The nickel capsule that one is equipped with dag is put in Oxygen-Azote mensuration instrument, measure peak and the nitrogen result of nickel capsule nitrogen, then standard model is loaded in a nickel capsule, with Crimping Pliers, nickel is encapsulated a mouthful compacting, measure peak and the nitrogen result of nitrogen, according to said method METHOD FOR CONTINUOUS DETERMINATION standard specimen more than three times, different measured value can be obtained, click the calibration of the nitrogen in the calibration of the instrument page, instrument meeting automatic calibration, now there will be a new calibration factor, click and preserve, next step, take sample to be tested, load in a nickel capsule, with Crimping Pliers, nickel is encapsulated a mouthful compacting, measure peak and the nitrogen result of nitrogen, the analysis result of nitrogen can be obtained, measure with standard specimen thus and contrast, accuracy of measurement.

Wherein said Oxygen-Azote mensuration instrument is that the U.S. makes every effort to overcome TC-600 Oxygen-Azote mensuration instrument or TC-500 Oxygen-Azote mensuration instrument.

Wherein said sample to be tested measures front ether and cleans.

Wherein said standard specimen is determined as three times.

Wherein said instrument parameter is set to:

PreAnalysis Purge Time:60 second; The shortest analysis time: 60 seconds; Integrated delay: 15 seconds; Comparer level: 3.00; Stove controls: power; Exhaust high power: 5500W; Exhaust low-power: 5500W; Analyze high power: 5000W; Analyze low-power: 5000W; Purge time: 15 seconds.

The invention difference from existing technology is that the present invention achieves following technique effect:

1. the present invention has formulated the assay method of nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys, can be used for production testing, Instructing manufacture technique.

2. the inventive method is stable, accurately, operating process is short, and cost is low, fast, efficiently, is easy to grasp.

Accompanying drawing explanation

Fig. 1 is the mensuration figure of blank test nitrogen;

Fig. 2 is the mensuration figure of a Nd Fe B alloys sample nitrogen;

Fig. 3 is Fig. 2 sample standard curve map;

Fig. 4 is the mensuration figure of the substandard sample nitrogen of Fig. 3;

Fig. 5 to be standard specimen nitrogen be 0.0081% peak value figure;

Fig. 6 to be standard specimen nitrogen be 0.0045% peak value figure;

Fig. 7 and Fig. 8 measures the peak value figure that sample G4-42 nitrogen is respectively 0.00909% and 0.00916%;

Fig. 9 and Figure 10 measures the peak value figure that sample G4-43 nitrogen is respectively 0.00815% and 0.00788%.

Embodiment

Below in conjunction with embodiment, to above-mentioned being described in more detail with other technical characteristic and advantage of the present invention.

1: instrument and principle

Oxygen-Azote mensuration instrument: the U.S. makes every effort to overcome TC-600 Oxygen-Azote mensuration instrument or TC-500 Oxygen-Azote mensuration instrument.

Instrument adopts helium or argon gas to do carrier gas, and sample high-temperature fusion under inert atmosphere in graphite crucible, the nitrogen in sample flows through conductance cell, according to the difference of thermal conductivity coefficient, detects the content of nitrogen, and converting through data processing becomes the content of nitrogen in sample.

2: reagent

Ether (analyzing pure);

Carrier gas (high-purity helium, purity is greater than 99.999%);

Power gas (ordinary nitrogen);

Graphite crucible (require good compactness, graphite purity is high)

Dag;

Nickel capsule;

3: sample size: sample needs, with ether cleaning, to take about 0.05g.

4: instrument parameter:

Release: 2

Analyze time delay comparer: 1

Analysis type: manual analyzing or automatic analysis

PreAnalysis Purge Time:60 second

The shortest analysis time: 60 seconds integrated delay: 15 seconds comparer levels: 3.00

Stove controls: power exhaust high power: 5500W is vented low-power: 5500W

Analyze high power: 5000W and analyze low-power: 5000W purge time: 15 seconds

5: blank:

Sample specimens amount is less, and in order to nitrogen content in Accurate Determining rare earth material Nd Fe B alloys, the blank value obtaining low and stable nitrogen is necessary, and the blank value of nitrogen is by nickel capsule, and crucible, oven cavity atmosphere causes, negligible through testing.In operation pages: click method, input above-mentioned instrument parameter, after preservation, in operation pages, the name of an article: input is blank, weight: input 1.000 grams, by burner lower button, bottom electrode falls, put graphite crucible, press burner lower button again, bottom electrode closes, carry out degassed to crucible, when page lower left occurs that prompting loads sample, press burner lower button again, bottom electrode falls, now analysis margin does not need setting-out, only put the nickel capsule that is equipped with a little dag, press burner lower button again, bottom electrode closes, instrument automatic analysis.There will be peak and the nitrogen result of nitrogen at the page, result nitrogen is about 0.00001%.Therefore negligible.

Before starting analytical sample as shown in Figure 1, first in blank, by aforesaid operations, can obtain peak and the blank value of figure empty, in figure, the measured value of nitrogen is-0.00002%, therefore negligible at every turn.

6: calibration:

In rare earth permanent-magnetic material Nd Fe B alloys, the mensuration of nitrogen does not have method and corresponding reference material, and in overtesting ferrous materials, in nitrogen and rare earth material Nd Fe B alloys, the release rate of nitrogen is substantially close.The fusing point of neodymium iron boron is 1170 DEG C, therefore, adopts ferrous materials nitrogen reference material Criterion curve, according to content and the integral area of testing sample, selects the standard specimen of close integral area to calibrate.First: method is set as manual operation, by above-mentioned parameter setting instrument, standard specimen in the page is clicked, after being inputted by the nitrogen content of selected standard specimen.In operation pages name of an article input standard specimen numbering, put after a nickel capsule that a little dag is housed weighs in external balance, zero, takes off.Then take standard specimen about 0.05 gram, by enter key, sample is loaded in nickel capsule, with Crimping Pliers, nickel is encapsulated a mouthful compacting.By burner lower button, bottom electrode falls, and puts graphite crucible, press burner lower button again, bottom electrode closes, and carries out degassed to crucible, when page lower left occurs that prompting loads sample, press burner lower button again, bottom electrode falls, and the nickel capsule that sample is housed of compacting is just now put into crucible, presses burner lower button again, bottom electrode closes, instrument automatic analysis.Peak and the nitrogen result of nitrogen is there will be at the page.According to said method METHOD FOR CONTINUOUS DETERMINATION standard specimen three times, can obtain three each precision and well be worth.Now choose this three values, click the calibration of nitrogen in page calibration, instrument can automatic calibration, now there will be a new calibration factor, clicks and preserve.Next step, take sample to be determined, equally operate as stated above, can obtain the analysis result of nitrogen.

As shown in Figure 2, by the operation of aforesaid operations step, the METHOD FOR CONTINUOUS DETERMINATION value obtaining (501-644 makes every effort to overcome standard specimen) nitrogen is 0.00906%, 0.00914%, 0.00928%, 0.00903%, obtain values of nitrogen might, standard deviation is 0.000013%, and relative standard deviation is 1.255%.General Requirements relative standard deviation <5%, so can choose this four standard specimens with upper figure, calibrates.All to calibrate before making sample, to reach the error that the drift that rectifies an instrument brings at every turn.Each coefficient is all different, and canonical plotting as shown in Figure 3.

As shown in Figure 4, calibrate the mensuration of laggard rower sample (peak value figure respectively as shown in Figure 5 and Figure 6 for standard value nitrogen=0.0081%, standard value nitrogen=0.0045%), obtaining measured value is respectively 0.00830%, 0.00458%, error ± 0.0004%.Measuring sample G4-42 nitrogen was 0.00909% and 0.00916% (as shown in Figure 7 and Figure 8), and sample G4-43 nitrogen was 0.00815% and 0.00788% (as shown in Figure 9 and Figure 10).Can average and quote result.Coefficient after calibration meets standard specimen measured value in error range, can be effective, otherwise will again calibrate.

7: sample measured result;

As can be seen from the above data: method has good stability, production requirement can be met.

This method Oxygen-Azote mensuration instrument, thermal conductivity method carries out the mensuration of quantitative test to nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys.Operating process is short, and cost is low, fast, accurately, efficiently, is easy to grasp, in can producing preferably.

Above-described embodiment is only be described the preferred embodiment of the present invention; not scope of the present invention is limited; under not departing from the present invention and designing the prerequisite of spirit; the various distortion that those of ordinary skill in the art make technical scheme of the present invention and improvement, all should fall in protection domain that claims of the present invention determines.

Claims (5)

1. utilize thermal conductivity method to measure a method for nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys, it is characterized in that it comprises the following steps:

The nickel capsule that one is equipped with dag is put in Oxygen-Azote mensuration instrument, measure peak and the nitrogen result of nickel capsule nitrogen, then standard model is loaded in a nickel capsule, with Crimping Pliers, nickel is encapsulated a mouthful compacting, measure peak and the nitrogen result of nitrogen, according to said method METHOD FOR CONTINUOUS DETERMINATION standard specimen more than three times, different measured value can be obtained, click the calibration of the nitrogen in the calibration of the instrument page, instrument meeting automatic calibration, now there will be a new calibration factor, click and preserve, next step, take sample to be tested, load in a nickel capsule, with Crimping Pliers, nickel is encapsulated a mouthful compacting, measure peak and the nitrogen result of nitrogen, the analysis result of nitrogen can be obtained, measure with standard specimen thus and contrast, accuracy of measurement.

2. the method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys according to claim 1, is characterized in that: described Oxygen-Azote mensuration instrument is that the U.S. makes every effort to overcome TC-600 Oxygen-Azote mensuration instrument or TC-500 Oxygen-Azote mensuration instrument.

3. the method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys according to claim 1, is characterized in that: described sample to be tested measures front ether and cleans.

4. the method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys according to claim 1, is characterized in that: described standard specimen is determined as three times.

5. the method utilizing thermal conductivity method to measure nitrogen content in rare earth permanent-magnetic material Nd Fe B alloys according to claim 1, is characterized in that: described instrument parameter is set to:

PreAnalysis Purge Time:60 second; The shortest analysis time: 60 seconds; Integrated delay: 15 seconds; Comparer level: 3.00; Stove controls: power; Exhaust high power: 5500W; Exhaust low-power: 5500W; Analyze high power: 5000W; Analyze low-power: 5000W; Purge time: 15 seconds.