GB/T 4698.17-2019Methods for chemical analysis of titanium sponge, titanium and titanium alloys—Part 17:Determination of magnesium content—Flame atomic absorption spectrometry (English PDF)

Foreword

GB/T 4698 "Methods for chemical analysis of titanium sponge, titanium and titanium alloys" consists of the following parts:

-- Part 1: Determination of copper content - Flame atomic absorption spectrometry;

-- Part 2: Determination of iron content;

-- Part 3: Determination of silicon content - Molybdenum blue spectrophotometry;

-- Part 4: Determination of manganese content-Potassium periodate spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 5: Determination of molybdenum content - Thiocyanate spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 6: Determination of boron content - Methylene blue spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 7: Determination of oxygen and nitrogen content;

-- Part 8: Determination of aluminum content - Separation with sodium hydroxide-EDTA complex-metric titration and inductively coupled plasma atomic emission spectrometry;

-- Part 9: Determination of tin content - Potassium iodate titration and inductively coupled plasma atomic emission spectrometry;

-- Part 10: Determination of chromium content - Ammonium ferrous sulfate titration and inductively coupled plasma atomic emission spectrometry (with vanadium;

-- Part 11: Determination of chromium content in the absence of Vanadium - Ammonium ferrous sulfate titration method;

-- Part 12: Determination of vanadium content - Ammonium ferrous sulfate titration and inductively coupled plasma atomic emission spectrometry;

-- Part 13: Determination of zirconium content - EDTA complexometric titration and inductively coupled plasma atomic emission spectrometry;

-- Part 14: Determination of carbon content;

-- Part 15: Determination of hydrogen content;

-- Part 16: Determination of oxygen content - Inert gas fusion coulometric method;

-- Part 17: Determination of magnesium content - Flame atomic absorption spectrometry;

-- Part 18: Determination of tin content - Flame atomic absorption spectrometry;

-- Part 19: Determination of molybdenum content - Thiocyanate-differential spectrophotometry;

-- Part 20: Determination of manganese content - Potassium periodate spectrophotometric method;

-- Part 21: Determination of manganese, chromium, nickel, aluminum, molybdenum, tin, vanadium, yttrium, copper and zirconium content - Atomic emission spectrometry;

-- Part 22: Determination of niobium content - 5-Br-PADAP spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 23: Determination of palladium content - Stannous chloride-potassium iodide spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 24: Determination of nickel content - Dimethylglyoxime spectrophotometry and inductively coupled plasma atomic emission spectrometry;

-- Part 25: Determination of chlorine content - Silver chlorin spectrophotometry;

-- Part 26: Determination of alloying elements and impurity elements - Inductively coupled plasma atomic emission spectrometry;

-- Part 27: Determination of neodymium content - Inductively coupled plasma atomic emission spectrometry;

-- Part 28: Determination of ruthenium content - Inductively coupled plasma atomic emission spectrometry;

-- Part 29: Determination of tungsten and tantalum - Inductively coupled plasma atomic emission spectrometry.

1 Scope

This Part specifies the determination method for magnesium content in titanium sponge, titanium and titanium alloys.

This Part is applicable to the determination of magnesium content in titanium sponge, titanium and titanium alloys. The determination range is 0.010%~1.00%.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 31981, Methods of sampling and sample preparation for chemical composition analysis of titanium and titanium alloy

3 Principle

Use hydrochloric acid and hydrofluoric acid to dissolve test material. Use boric acid complexes fluoride ions and strontium chloride as release agents. Use air-acetylene flame, at a wavelength of 285.2nm of atomic absorption spectrometer, to determine the magnesium content.

4 Reagents

Unless otherwise specified, the reagents used in this Part are analytical reagents and laboratory grade two water.

4.1 Hydrochloric acid (rho=1.19g/mL).

4.2 Nitric acid (rho=1.42g/mL).

4.3 Hydrofluoric acid (rho=1.15g/mL).

4.4 Hydrochloric acid (1+1).

4.5 Nitric acid (1+1).

4.6 Hydrofluoric acid (1+1).

4.7 Saturated boric acid solution.

5 Equipment

Atomic absorption spectrometer, with magnesium hollow cathode lamp.

Under the optimal working conditions of the instrument, anyone that can meet the following indicators can be used:

-- Characteristic concentration: In a solution consistent with the measurement solution matrix, the characteristic concentration of magnesium shall not be greater than 0.02µg/mL;

-- Precision: Use the highest concentration standard solution to measure absorbance 10 times. The standard deviation shall not exceed 1.0% of the average absorbance. Use the lowest concentration standard solution (not "zero" concentration standard solution) to measure absorbance 10 times.

The standard deviation shall not exceed 0.5% of the average absorbance of the highest concentration;

-- Working curve linear: Divide the working curve into five segments by concentration. The ratio of the absorbance difference between the highest […]