This standard specifies the determination method of oxygen content in copper and copper alloys. This standard is applicable to the determination of oxygen content in copper and copper alloys. Determination range: 0.000 30% to 0.11%. GB/T 5121.8-1996 Chemical analysis method for copper and copper alloys Determination of carbon and sulfur content GB/T5121.8-1996 Standard download decompression password: www.bzxz.net

1 Scope
National Standard of the People's Republic of China
Chemical analysis method for copper and copper alloys
Determination of oxygen content
Copper and copper alloys-Determination of oxygen content This standard specifies the method for determining the oxygen content in copper and copper alloys. GB/T 5121.8 --1996
Replaces GB 5121.8 85
This standard applies to the determination of oxygen content in copper and copper alloys. Determination range: 0.00030%~～0.11%. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards are subject to revision, and parties using this standard should explore the possibility of using the latest versions of the following standards. GB1.4-88 Standardization work guidelines for chemical analysis method standards GB1467-78 General principles and general provisions for chemical analysis method standards for metallurgical products GB/T14265-93 General principles for analysis of hydrogen, oxygen, nitrogen, carbon and sulfur in metal materials 3 Method summary
Put the pre-prepared sample into a graphite crucible degassed at high temperature, heat and melt in ammonia (or argon) gas flow, and the oxygen in the sample is... Carbon monoxide is precipitated or passed through a rare earth copper oxide furnace at 400°C with ammonia (or argon) gas to oxidize carbon monoxide into carbon oxide, which is introduced into an infrared detector for measurement. The computer automatically gives the oxygen content. 4 Reagents and materials
4.1 Nitrogen (or argon) gas: purity not less than 99.95%. 4.2 Power gas: nitrogen, fluorine gas or compressed air, with impurities (oil and water) less than 0.5%. 4.3 Anhydrous ethanol.
4.4 Rare earth copper oxide.
4.5 Anhydrous magnesium perchlorate.
4.6 Alkaline asbestos.
4.7 Glass wool.
4.8 Vacuum silicone grease.
4.9 Mixed acid: 28mL phosphoric acid (p1.69g/mL), 10mL nitric acid (pl.42g/mL) and 62mL glacial acetic acid (pl.05g/ml.) are mixed evenly.
Standard substance of oxygen in copper.
4.11 Graphite crucible: Made of high-purity or spectral pure graphite. Its shape and size refer to Figure 1. Other shapes and sizes of crucibles that can completely precipitate oxygen are allowed to be used, and the heating conditions are selected separately. Approved by the State Administration of Technical Supervision on November 4, 1996 232
Implemented on April 1, 1997
5 Instruments
5.1 Instrument performance
GB/T 5121.8 -1996
Figure 1 Schematic diagram of ink-free crucible
Pulse heating infrared absorption instrument (with electronic AC voltage regulator). The instrument should meet the following indicators: 5.1.1 Instrument sensitivity ≤ 0.00005%.
5.1.2 Pulse heating power is not less than 6.5kW (furnace temperature is not less than 2400℃). 5.1.3 System blank ≤ 0.00005%.
5.2 See Figure 2 for the schematic diagram of the instrument.
1-Hydrogen (or argon) gas; 2-Solenoid valve; 3-Catalytic heating furnace; 4-Alkaline asbestos; 5-Magnesium perchlorate; 6-Solenoid valve; 7-Pressure regulating valve; 8-Six-way valve; 9-Pulse heating furnace; 10-Glass wool; 11-Dilute copper oxide; 12-Flow controller: 13-CO, or CO) infrared detector Figure 2 Instrument schematic diagram
6 Sample www.bzxz.net
6.1 The sample is turned into a round rod or other small sample with a size of 3mm~$5mm and a length greater than 40mm. Do not overheat during heating to prevent oxidation
6.2 Use a special steel file and hand saw to process the sample into the required amount. 6.3 Place the sample in the mixed acid for corrosion for 10 minutes, take it out and quickly wash it with distilled water, then wash it with anhydrous ethanol, and analyze it immediately after drying it with cold wind.
6.4 If the sample is found to be oxidized, repeat the treatment according to 6.3. 233
7 Analysis steps
7.1 Test material
GB/T 5121.8 --- 1996
Weigh 0.30~1.00g of test material, accurate to 0.001g. Perform two independent measurements and take the average value. 7.2 Preparation of instrument
7.2.1 Prepare and calibrate the instrument according to the instrument manual: the instrument should be in normal condition before analysis. 7.2.2 Before analysis, calibrate with standard substance of oxygen in copper to determine the correction factor. The oxygen standard substance used should be close to the oxygen content of the sample being tested. The sample amount can also be controlled so that the absolute value of the oxygen content of the oxygen standard substance is close to the absolute value of the oxygen content of the sample being tested. 7.3 Blank test
Perform a blank test according to the conditions specified in 7.4.2. 7.4 Determination
7.4.1 Load the sample into the sampler, clean the pulse furnace with a special metal brush, load a new crucible, and follow the instrument operating procedures. 7.4.2 Instrument analysis conditions (recommended)
a) Degassing power 5500W (or 1100A); b) Analysis power 4500W (or 1000A); c) Analysis time 30$.
8 Expression of analysis results
The oxygen content (%) is automatically calculated by the computer. The result is expressed to two decimal places; if the oxygen content is less than 0.10%, it is expressed to 3 decimal places; if it is less than 0.010%, it is expressed to 4 decimal places; if it is less than 0.0010%, it is expressed to 5 decimal places. 9 Allowable difference
The difference between the analysis results of laboratories should not be greater than the allowable difference listed in Table 2. Table 2
0.00030~0.00050
>0.000 50~0. 001 0
≥0. 001 0~0. 005 0
>0. 005 0~ 0. 010
0. 010~~0. 040
0. 040-~ 0. 080
0. 080~ 0. 11
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