GB/T 14988-2008Hysteresis alloy (English PDF)

1 Chemical composition 1/furnace GB/T 2006 GB/T 223, GB/T 2023 or general method

2 Hysteresis performance GB/T 3657 and Appendix A in any part of the finished product

3 Dimensions and Shapes-Universal Measuring Tools

4 Surface quality by branch-visual inspection

7 Inspection rules

8 Packaging, marking and quality certificate

The packaging, marking and quality certificate of the finished alloy material shall comply with the relevant provisions of QB/T 5242.

Appendix A (Normative appendix)

Preparation of Hysteresis Alloy Samples and Testing and Calculation Methods of Hysteresis Parameters

A. 1 Sample preparation

A. 1.1 The specimen shall be made into a ring with an outer diameter of 40 mm and an inner diameter of 32 mm. The ratio of the average diameter to the radial width can also be used.

For other ring sizes of 8, the thickness of the ring is 2mm ~ 5mm. Hot rolled (forged) material with a diameter of less than 40 mm allows sampling on the intermediate billet.

For 2J25 and 2J27 alloys, rod-shaped samples are allowed for inspection, but the aspect ratio of the samples should not be less than 5. The two ends of the strip specimen shall be mutually

Parallel and perpendicular to the axis.

A. 1.2 The sample shall be flat, clean and free of burrs. After heat treatment, the oxide scale shall be removed.

A. 2 Testing and calculation methods of hysteresis parameters

A. 2.1 The cross-sectional area S0 of the ring sample is recommended to be calculated according to formula (A.1)

S0 = W/piagamma (A.1)

In the formula.

S0 --- cross-sectional area of the sample, in square meters (m2);

W --- sample mass, unit is kilogram (kg);

a --- average diameter of the sample, in meters (m);

gamma --- The density of alloy, the unit is kilogram per cubic meter (kg/m3).

If the above method is not used, the thickness of the sample can be measured piece by piece with a precision micrometer to calculate the cross-sectional area.

A. 2.2 The sample, measurement winding and magnetized winding shall be insulated from each other, and the measurement winding shall be wound on the inner layer.

A. 2.3 When testing, first determine the value of Hµ, and then make a hysteresis loop under this magnetic field to find other hysteresis parameters.

A. 2.4 Hysteresis parameters of the alloy are calculated according to formula (A.2) and formula (A.3).

Kµ = piPµ/HµBµ (A.3)

In the formula.

S --- The measured area of the hysteresis loop, the unit is square meter (m2);

Kµ --- the convex coefficient corresponding to the maximum magnetic permeability point;

Pµ --- the specific hysteresis loss corresponding to the maximum permeability point, the unit is kilojoules per cubic meter (kJ/m3);

Hµ --- the magnetic field strength corresponding to the maximum magnetic permeability point, the unit is kiloampere per meter (kA/m);

Bµ --- the magnetic flux density corresponding to the maximum magnetic permeability point, the unit is special (T).

Appendix B (Informative appendix)

Recommended heat treatment system for alloy samples

B. 1 The alloy cold rolled strip samples are recommended according to Table B. 1 prescribed heat treatment system.

Table B. 1

Alloy grade tempering temperature/°C holding time/min cooling method

2J4 600 ~ 660

2J7 580 ~ 660

2J9 580 ~ 640

2J10 580 ~ 640

2J11 580 ~ 640

2J12 580 ~ 640

2J53 500 ~ 560

20 ~ 60 air cooling

B. 2 The alloy hot forging (rolling) sample is recommended according to Table B. 2 prescribed heat treatment system.

Table B. 2

Alloy grade

Quenching and tempering

Heating temperature/°C (In a protective atmosphere)

Holding time / min

Quenching medium

Tempering temperature /

Holding time / min cooling method

2J21 12200 ± 10

2J23 12200 ± 10

2J25 1250 ± 10

2J27 1250 ± 10

15 ~ 30 oil or boiling water

625 ~ 700

625 ~ 700

625 ~ 725

625 ~ 725

60 ~ 120 air cooling

Appendix C (Informative appendix)

Other properties of the alloy

C. 1 Other properties of the alloy are listed in Table C. 1.

Table C. 1

Alloy grade density

gamma / (G/cm) 3

Curie Point

Tc /

Thermal expansion coefficient

alpha (20 °C ~ 300 °C)

× 10-/6/°C

Resistivity

rho / (Mohm. cm)

Young's modulus

E /

MPa hardness

HRC 2J4 8.2 8600 10.70 33 33 18,000-

2J7 8.1 860 10.60 60 1 18000-

2J9 8.1 8600 10.60 65 18,000-

2J10 8.1 8660 11.30 30 1 19,000-

2J11 8.1 8660 11.2 07 7 17,000-

2J12 8.1 8660 13.40 74 17,000-

2J21 8.8.2 8220 11.24 34 35 22000 35 ~ 42

2J23 8.3 8220 11.1 10 37 37 21000 35 ~ 42

2J25 8.3 820 11.11.18 42 210,000 3500 35 ~ 42

2J27 8.4 820 11.12 21 38 38 20,000 35 ~ 42

2J53 7.8-15.50 61 17,000- […]