GOST 9721-79
GOST 9721−79 cobalt Powder. Specifications (with Amendments No. 1, 2, 3, 4)
GOST 9721−79
Group 56
STATE STANDARD OF THE USSR
COBALT POWDER
Specifications
Cobalt powder. Technical requirements
GST 17 9350
Date of introduction 1981−01−01
INFORMATION DATA
1. DEVELOPED AND INTRODUCED by the Ministry of nonferrous metallurgy of the USSR
DEVELOPERS
R. S. Maizlish, PhD. tech. Sciences; A. I. Vereshchagin, V. L. Kremnev
2. APPROVED AND put INTO EFFECT by Decision of the USSR State Committee for standards from
3. REPLACE GOST 9721−71
4. REFERENCE INFORMATION AND TECHNICAL PAPERS
| The designation of the reference document referenced |
The number of the paragraph, subparagraph |
| GOST 12.1.005−88 |
2.2 |
| GOST 12.1.007−76 |
2.1 |
| GOST 503−81 |
5.2 |
| GOST 741.1−80 |
4.2.2 |
| GOST 741.3−80 |
4.3 |
| GOST 2991−85 |
5.2 |
| GOST 3560−73 |
5.2 |
| GOST 5556−81 |
4.2.3 |
| GOST 6613−86 |
4.4 |
| GOST 6128−75 |
5.1 |
| GOST 8776−79 |
4.3 |
| GOST 10727−91 |
4.2.3 |
| GOST 14192−96 |
5.5 |
| GOST 15846−79 |
5.2 |
| GOST 18318−94 |
4.4 |
| GOST 19433−88 |
5.5 |
| GOST 19440−94 |
4.2.3 |
| GOST 20461−75 |
4.2.3 |
| GOST 21140−88 |
5.2 |
| GOST 21241−89 |
4.2.3 |
| GOST 23148−78 |
4.2.3 |
| GOST 25086−87 |
4.2.3 |
| GOST 25336−82 |
4.2.3 |
| GOST 29298−92 |
4.2.3 |
| THAT 6−09−3880−75 |
4.2.3 |
| THAT 6−09−4120−75 |
4.2.3 |
| THAT 16−538−322−78 |
4.2.3 |
| THAT 25−1894.003−90 |
4.2.3 |
5. REVISED (June 1997) with Amendments No. 1, 2, 3, 4, approved in March 1981, August 1985, July 1990, February 1993 (IUS 6−81, 11−85, 10−90, 9−93)
This standard applies to cobalt powder, manufactured by electric method and intended for the production of products by powder metallurgy and magnets.
The standard does not apply to cobalt powder obtained by recovery of cobalt compounds.
(Changed edition, Rev. N 2).
1. MARKS AND TECHNICAL REQUIREMENTS
1.1. Cobalt powder must be made in accordance with the requirements of this standard for technological regulations approved in the prescribed manner. Depending on the chemical composition of cobalt powder manufactured brands of PC-1U.
(Changed edition, Rev. N 2).
1.2. The chemical composition of the powder should match what is specified in the table.1.
Table 1
| Brand powder | Chemical composition, % |
OKP code | |||||
| Cobalt, not less | Impurity, not more than |
||||||
| Iron |
Silicon | Nickel | Carbon | Copper | |||
| PK-1U |
The 99.35 | 0,2 | 0,02 | 0,4 | 0,02 | 0,04 | 17 9351 0001 |
(Changed edition, Rev. N 3, 4).
1.3. Mass fraction of moisture and oxygen in the powder must not exceed: moisture — 0,15%; oxygen, 0.3 percent.
(Changed edition, Rev. N 4).
1.4. The particle size of the powder should be less than 71 microns. Presence of powder particles larger than 71 µm in an amount of not more than 4% by weight of the party.
Mass fraction of powder particles with a size less than 45 microns must be at least 30% by weight of the party.
1.5. The bulk density of the powder is determined by user demand.
(Changed edition, Rev. N 2).
2. SAFETY REQUIREMENTS
2.1. In accordance with the requirements of GOST 12.1.007 the degree of impact on the human body cobalt powder refers to 2 hazard class.
2.2. The maximum permissible concentration of cobalt powder in the working zone air according to GOST 12.1.005 — 0.5 mg/m.
2.3. The maximum permissible concentration of cobalt ions in water is 1.0 mg/DM.
The cobalt content in the water is determined by the photometric method in the scientific and technical documentation approved in the established order, or other methods of equal precision photometric.
2.4. In aerial environment and waste waters in the presence of other substances or factors of the cobalt powder of toxic substances does not form.
2.5. Cobalt powder under normal conditions is not flammable (ignition temperature 370 °C), fire — and explosion.
Sec. 2. (Changed edition, Rev. N 2).
3. ACCEPTANCE RULES
3.1. Cobalt powder take parties. The party should be decorated by one document on quality. The weight of the batch should not exceed 500 kg. the Document about quality should contain:
trademark or a trademark and the name of the manufacturer;
the name and brand of the product;
batch number;
number of seats in the party;
the results of the tests;
the date of issue;
the designation of this standard.
(Changed edition, Rev. N 3).
3.2. To check the quality of powder with the requirements of this standard and the integrity of packaging from batch take a sample at the table.2.
Table 2
| Number of packing units in the batch |
The sample size | |||
| From | 1 | to | 5 | All |
| « | 5 | « | 15 | 5 |
| « | 15 | « | 35 | 7 |
| « | 35 | « | 60 | 8 |
| « | 60 | « | 99 | 9 |
Note. Every subsequent 100 packaging units of the party take one packaging unit.
(Changed edition, Rev. N 2).
3.3. If unsatisfactory results at least in one of the figures on it, repeat tests are carried out at twice the sample taken from the same batch. The results of repeated tests apply to the entire party.
3.4. Mass fraction of impurities is provided by manufacturing technology and are determined periodically, at least once a quarter or at the request of the consumer.
(Added, Rev. N 3).
4. TEST METHODS
4.1. Sampling and sample preparation
4.1.1. Sampling — according to GOST 23148*.
______________
* On the territory of the Russian Federation GOST 23148−98. — Note the manufacturer’s database.
4.1.2. Selected spot samples are thoroughly mixed, the resulting merged sample kvantovanie to reduce a mass of at least 500 g.
(Changed edition, Rev. N 2).
4.1.3. The received sample is divided into two parts. One part is subjected to tests, the other is Packed in tightly sealed jars and store for 1 year in case of disagreements in quality assessment. Each Bank must be provided with a label, which indicate:
the name of the manufacturer;
the name of the product;
batch number;
the date of sampling.
(Changed edition, Rev. N 3).
4.2. Determination of moisture and oxygen to automatic analyzer
4.2.1. The essence of the method
The method of determining the mass fraction of moisture based on sample dried cobalt powder for 1 min at 100−120 °C in a helium current. Mass loss of the sample during drying is proportional to the moisture content in the powder.
The method of determining the mass fraction of oxygen based on a reaction between the dissolved and bound oxygen in the sample with carbon in the graphite crucible at the temperature of the melt (2000−2800 °C) in flowing helium with the formation of carbon monoxide (II). The gas mixture passes through a column of heated copper oxide (II), where the oxidation of carbon monoxide (II) to carbon monoxide (IV). The gas stream containing carbon oxide (IV), passes through a thermal conductivity detector. The change of thermal conductivity of the gas mixture is proportional to the oxygen content in the sample. By comparison, gas is helium, is directed as a separate stream into the detector.
4.2.2. General requirements and safety requirements — according to GOST 741.1*
________________
* In part of sec. 1 replaced GOST 13047.1−2002, except for sec. 1 replaced GOST 13047.3−2002. — Note the manufacturer’s database.
4.2.3. Equipment, reagents
Analytical analyzer with all accessories, providing the metrological characteristics that are not inferior are given in table.3.
Laboratory scales General purpose type VLR-200 g or similar type.
The regulator voltage of 220−380 V.
Standard samples of enterprises of the composition of the Nickel or cobalt powder or state standard samples of composition of the steel SG-10.
Standard samples of composition (COC) conforming to the analyzer.
Stopwatch on the other 25−1894.003.
Crucibles, graphite on the other 16−538−322.
Hydraulic press, providing the effort is not less than 1500 N.
Press form steel punch with a diameter of 5−6 mm, a height of 50−60 mm.
Tweezers plastic.
Medical forceps according to GOST 21241.
Desiccator, 2−100, 2−250 2−140 or GOST 25336.
Askara on the other 6−09−4128.
Magnesium perchlorate (anhydro) TU 6−09−3880.
Helium gas according to GOST 20461.
The technical rectified ethyl alcohol according to GOST 18300.
The optical fiber according to GOST 10727.
Medical absorbent cotton wool GOST 5556.
Fabric: cotton, coarse calico group according to GOST 29298*.
______________
* On the territory of the Russian Federation GOST 29298−2005. — Note the manufacturer’s database.
To determine the moisture analyzer is required to connect the power transformer to the furnace through the voltage regulator for regulation of small currents.
4.2.4. Analysis
4.2.4.1. The inclusion of the analyzer, its warming-up, calibration and execution of the analysis carried out according to the instruction manual of the analyzer.
The definition of amendments the reference experiment is carried out in accordance with the «Manual for the laboratory manual for the Eclipse». The value of the reference experiment shall not exceed 4·10%.
4.2.4.2. In the analysis of cobalt powder on the moisture content in a graphite crucible weighed 1,5000−2,5000 grams of powder and placed in an oven gas analyzer. For 1 min the sample is dried in a current of helium at a temperature of 100−120 °C. Then, the graphite crucible and weighed again weighed. It is necessary to consider the amendment in the reference experiment. To do this, weigh three empty crucible, dried at the same conditions, re-weighed, the result is averaged.
4.2.4.3. In the analysis of cobalt powder to the oxygen content of take the weight and mass of 0,150−0,200 g in powder form or compressed into a tablet. In this case, the compensator weight of the detector is exhibited in the magnitude of 2−3 times more than the value of the sample. Readings of the voltmeter (the oxygen content percentage) should also be increased in 2−3 times, respectively.
At the end of the analysis to determine the rate of extraction, which should not exceed the value of the reference experience.
4.2.4.4. Processing of the results
Mass fraction of moisture () in percent is calculated by the formula
where — weight of powder before drying, g;
— weight of powder after drying, g.
Mass fraction of oxygen in the powder is determined by the readings of the digital voltmeter percent.
For the results analysis be the arithmetic mean of results of three parallel measurements the mass fraction of moisture and oxygen.
4.2.4.5. Allowable absolute discrepancies in the results of parallel measurements characterizing the convergence of the method for determination of moisture and oxygen (), and the results of two analyses that characterize the repeatability of the method (a
), shall not exceed the values given in table.3.
Table 3
| Mass fraction, % | The acceptable absolute differences, % | |||||
| Moisture |
||||||
| From | 0,020 | to | 0,040 | incl. | 0,012 |
- |
| SV. | 0,040 | « | 0,100 | « | 0,021 |
- |
| « | 0,10 | « | 0,20 | « | 0,03 |
- |
| Oxygen |
||||||
| From 0.18 to 40 |
0,02 | 0,02 | ||||
4.2.4.6. Accuracy control in the determination of moisture — according to GOST 25086.
Accuracy control in the determination of oxygen is carried out at SOS.
Analysis of SOS is carried out once a month at the same time with the batch of samples.
4.2−4.2.4.6. (Changed edition, Rev. N 4).
4.3. Mass fraction of iron, silicon, Nickel and copper is determined by spectral analysis according GOST 8776*.
______________
* On the territory of the Russian Federation GOST 8776−99. — Note the manufacturer’s database.
Mass fraction of carbon is determined according to GOST 741.3*.
______________
* On the territory of the Russian Federation GOST 13047.6−2002. — Note the manufacturer’s database.
Mass fraction of cobalt find the difference between 100% and the sum of the content of the regulated contaminants listed in the table.1.
(Changed edition, Rev. N 1, 2, 3, 4).
4.4. Particle size distribution of the cobalt powder determined according to GOST 18318, with the following addition: allowed determination of granulometric composition on the meshes of the sieves according to GOST 6613.
(Changed edition, Rev. N 1).
4.5. The bulk density of the cobalt powder determined according to GOST 19440.
4.6. Allowed in determining the mass fraction of impurities, moisture and oxygen, particle size distribution and bulk density of the cobalt powder to use other methods, accuracy is not inferior to the specified in the standard. The differences in the assessment of the quality of the cobalt powder used methods specified in the standard.
(Changed edition, Rev. N 3, 4).
5. PACKING, MARKING, TRANSPORTATION AND STORAGE
5.1. Cobalt powder is Packed in metal cans according to GOST 6128* or in plastic bottles with a capacity of not more than 10 DMin the normative-technical documentation. By agreement with the consumer packaging of powder in other types of containers, made according to normative-technical documentation.
______________
* On the territory of the Russian Federation GOST 6128−81. — Note the manufacturer’s database.
The packaging should be airtight. Jars and bottles filled with powder it is possible more densely to reduce the volume of air above the powder.
(Changed edition, Rev. N 1, 2).
5.2. Cans and bottles are further Packed in thick wooden boxes with lids of types I-IV according to GOST 2991, whose sizes according to GOST 21140. The bottles are Packed using packing materials or boxes with partitions.
Boxes should be covered with belts of steel packing tape according to GOST 503, or according to GOST 3560, the ends of which are fastened to the castle.
During transportation of the powder in the far North and in remote areas packaging must meet the requirements of GOST 15846*.
______________
* On the territory of the Russian Federation GOST 15846−2002. — Note the manufacturer’s database.
(Changed edition, Rev. N 1).
5.3. The gross weight of wooden boxes must not exceed 50 kg. By agreement with the consumer allowed gross mass wooden box not more than 80 kg.
5.4. Cans and bottles are labeled with paper labels with the application the following data:
trademark or a trademark and the symbol of the manufacturer;
the name and brand of product;
batch number;
rooms cans (bottles);
the weight of the powder;
date of issue;
designation of this standard;
sign «Sealed package».
5.5. Transport marking under GOST 14192. Sign of danger according to GOST 19433, grade 9, category 915, classification code 9153.
(Changed edition, Rev. N 2, 4).
5.6. Packed powder is transported by all types of transport in covered vehicles in accordance with cargo carriage regulations applicable to transport of this species.
(Changed edition, Rev. N 2).
5.7. Powder should be stored in closed heated premises in packing of manufacturer.
6. MANUFACTURER’S WARRANTY
6.1. The manufacturer must guarantee the conformity of the cobalt powder with the requirements of this standard if the conditions of transportation and storage.
6.2. Warranty period of storage of the cobalt powder 1 year from the date of manufacture.
(Changed edition, Rev. N 3).
6.3. (Deleted, Rev. N 2).
