GB/T 25080-2022Specification for niobium-titanium alloy billets and bars for superconducting applications (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 25080-2010 "Nb-Ti Alloy Billets, Thick Rods and Thin Rods for Superconductivity", which is consistent with GB/T 25080-2010 In addition to structural adjustments and editorial changes, the main technical changes are as follows.

--- Added specific provisions for the upper limit of the size of the defect. 3%D or 2.5mm (see 7.3);

--- Added "cracks", "black skin" and "scratch" to the list of "harmful defects", deleted "scars", "burrs" and "scuffs" (see 10.1, 2010 10.1 of the year edition);

--- Increased the detection method of surface roughness (see 14.6);

--- Change "the frequency of the conventional probe should be 2.25MHz~10MHz" to "the minimum nominal frequency of the probe should be 2.25MHz" (see A.2.1.2, A.2.1.2 of the 2010 edition).

Introduction

Niobium-titanium (Nb-Ti) superconducting material is by far the most widely used superconducting material. Nb-Ti alloy billets and bars are machined Nb- The quality of the raw material of Ti superconducting wire plays a decisive role in the quality of the final Nb-Ti superconducting product. Therefore, in order to adapt to domestic super To meet the needs of the rapid development of conductive technology, unify and standardize the technical requirements, test methods, and acceptance regulations for domestic Nb-Ti alloy billets and bars for superconductivity.

GB/T 25080-2010 needs to be revised, so as to form superconducting products that are basically consistent with foreign advanced standards Specification standard for Nb-Ti alloy billets and bars.

This document was drafted with reference to the American Society for Testing and Materials Standard ASTMB884-2019 "Nb-Ti Alloy Rods for Superconductivity" redefines.

1 Scope

This document specifies the technical requirements, test methods, acceptance rules, marking and packaging of niobium-titanium (Nb-Ti) alloy billets and bars for superconductivity Install and so on.

This document is applicable to Nb-Ti alloy billets and bars containing Ti46%~48% (mass fraction) for the manufacture of superconducting wires.

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 4340.1 Vickers Hardness Test for Metal Materials Part 1: Test Methods

GB/T 6060.2 Surface roughness comparison sample block grinding, turning, boring, milling, inserting and planing surface

GB/T 6394 Metal Average Grain Size Determination Method

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

GB/T 9445 Qualification and Certification of Nondestructive Testing Personnel

GB/T 18851.1 Nondestructive Testing Penetrant Testing Part 1: General

JB/T 10061 General technical conditions of A type pulse reflection ultrasonic flaw detector

3 Terms and Definitions

The following terms and definitions apply to this document.

4 Order Information

Orders placed under this document shall include the following. […]