GB/T 4296-2022Inspection method for microstructure of wrought magnesium alloy (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for Standardization Work Part 1: Structure and Drafting Rules of Standardization Documents" drafted.

This document replaces GB/T 4296-2004 "Microstructure Inspection Method of Wrought Magnesium Alloys". Compared with GB/T 4296-2004, except for In addition to structural adjustments and editorial changes, the main technical changes are as follows.

a) The terms and definitions of "grain size" and "G value" are deleted (see Chapter 2 of the.2004 edition);

b) Added the types of etchants (see Table 1);

c) Added the applicable test for etchants (see Table 2);

d) The requirements for the inspection surface of the sample are added (see 5.3);

e) The requirements for specimen polishing have been added (see 5.6);

f) Changed the requirements for rough throwing (see 5.7.1, 3.5.1 of the.2004 edition);

g) Changed the requirements for fine throwing (see 5.7.2, 3.5.2 of the.2004 edition);

h) Changed the requirements for fine polishing (see 5.7.3, 3.5.3 of the.2004 edition);

i) Added optical microstructure pictures of typical products (see 7.2);

j) Added scanning electron microscope tissue observation pictures (see 7.3).

1 Scope

This document specifies the test solution, sample preparation, sample etching, microstructure inspection, and grain size determination of wrought magnesium alloys. Methods and test report content.

This document is applicable to the inspection of the microstructure of wrought magnesium alloy ingots (or ingots) and processed products.

2 Normative references

The contents of the following documents constitute essential provisions of this document through normative references in the text. Among them, dated citations documents, only the version corresponding to that date applies to this document; for undated references, the latest edition (including all amendments) applies to this document.

GB/T 8170-2008 Numerical Rounding Rules and Representation and Judgment of Limit Values

3 Terms and Definitions

There are no terms and definitions that need to be defined in this document.

4 Test solution

The test solution and preparation method are shown in Table 1.

1 Polishing liquid

Glycerol (rho1.261g/mL), hydrochloric acid (rho1.19g/mL), nitric acid (rho1.40g/mL), acetic acid (rho1.049g/mL) were mixed with 20.2.3.5 by volume, mix well

2 Etchant No. 1

Weigh 1g of oxalic acid in a container, add 150mL of distilled water (or deionized water), 1mL of nitric acid (rho1.40g/mL), 1mL acetic acid (rho1.049g/mL)

3 Etchant No. 2

Weigh 3 g of trinitrophenol (picric acid) into a container, add 20 mL of distilled water (or deionized water), 50 mL of anhydrous ethyl acetate in turn. Alcohol (rho0.789g/mL), 20mL acetic acid (rho1.049g/mL)

4 Etching agent No. 3 Mix nitric acid (rho1.40g/mL) and anhydrous ethanol (rho0.789g/mL) in a volume of 1.19, and mix well.

5 Etchant No. 4

Weigh 0.5g of oxalic acid in a container, add 97mL of distilled water (or deionized water), 1mL of nitric acid (rho1.40g/mL), 1mL acetic acid (rho1.049g/mL)

6 Etchant No. 5 Weigh 2g of oxalic acid in a container, add 100mL of distilled water (or deionized water) Etchant No. 6 (thin film etchant)

Weigh 6g picric acid in a container, add 1mL distilled water (or deionized water), 100mL absolute ethanol (rho0.789g/mL), 2mL acetic acid (rho1.049g/mL), 0.5mL phosphoric acid (rho1.70g/mL)