JB/T 1460-2011Rolling bearings - Parts made of high-carbon chromium stainless steel - Technical specifications for heat treatment (English PDF)

Foreword

This standard replaces JB/T 1460-2002 "Specifications for heat-treatment of rolling bearing parts made from high carbon chromium stainless steel".

As compared with JB/T 1460-2002, the main changes of this standard are as follows.

- MODIFY the standard name (Cover and first page of the 2002 version and this version);

- ADD the steel grade G65Cr14Mo (Clause 1 of this version);

- MODIFY the hardness values of the bearing parts after tempering (Clause 3.1.1 of this version; Table 1 of the 2002 version);

- MODIFY the partial quenched and tempered microstructure rating image (Level II diagram of this version and the 2002 version);

- ADD the requirements for tempering stability of bearing parts (Clause 3.2.6 of this version);

- LIST the description of the microstructure level diagram in the Appendix (Appendix E of this version, a) ~ f) in clause 3.2.2.3 of the 2002 version).

Appendix A, Appendix B, Appendix C and Appendix D of this standard are normative appendixes. Appendix E is an informative appendix.

1 Scope

This standard specifies the technical requirements, inspection methods and rules for the annealed and quenched & annealed stainless steel rolling bearing rings and rolling elements (hereinafter referred to as bearing parts) which are made from G95Cr18 (original designation 9Cr18), G102Cr18Mo (original designation 9Cr18Mo), G65Cr14Mo that comply with the provisions of GB/T 3086-2008.

This standard applies to the heat-treatment quality inspection of bearing parts made of the above materials.

2 Normative references

The provisions in following documents become the provisions of this standard through reference in this standard. For the dated references, the subsequent amendments (excluding corrections) or revisions do not apply to this Standard; however, parties who reach an agreement based on this standard are encouraged to study if the latest versions of these documents are applicable.

For undated references, the latest edition of the referenced document applies.

GB/T 230.1-2009 Metallic materials - Rockwell hardness test - Part 1: Test method (scales A, B, C, D, E, F, G, H, K, N, T)

GB/T 231.1-2009 Metallic materials - Brinell hardness test - Part 1: Test method

GB/T 3086-2008 High carbon chromium stainless bearing steels

GB/T 4340.1-2009 Metallic materials - Vickers hardness test - Part 1: Test method

JB/T 1255-2001 Specification for heat-treatment of rolling bearing parts made from high carbon chromium steel

JB/T 7361-2007 Rolling bearings -

3 Technical requirements

4 Inspection methods and rules

In accordance with the model, specification and quantity of each batch of bearing parts, a certain proportion of bearing parts shall be taken for inspection.

The inspection method shall be in accordance with Table 3. If the manufacturer can guarantee that the bearing parts fracture and corrosion resistance are qualified, it can be exempted from the inspection.

Inspection item Inspection methods Hardness Hardness test can be performed in accordance with the hardness and size of the tested parts using the Brinell, Rockwell, Vickers or Leeb hardness tester, the test methods shall be in accordance with the provisions of GB/T 231.1-2009, GB/T 230.1-2009, GB/T 4340.1 -2009 and JB/T 7361-2007 For the steel balls with a nominal diameter Dw >= 4.762 mm (3/16 in), the hardness is measured on the spherical surface. For a roller with an effective diameter >= 5 mm, the hardness is measured on a cylindrical or conical surface; for the steel ball with a nominal diameter Dw < 4.762 mm (3/16 in) and the roller with an effective diameter < 5 mm, the Vickers hardness is measured on the grinding plane. Vickers hardness and Rockwell hardness are converted in accordance with GB/T 1172-1999; Spherical roller hardness is measured at the end surface.

Appendix C (Normative) Pickling test procedures

Appendix E (Informative)

Quenched and tempered microstructure level diagram descriptions The quenched and tempered microstructure level diagram (see the level II diagram) is described as follows.

a) First level. Martensite + a large number of residual secondary carbides and primary carbides + a small amount of residual austenite This structure is formed at the lower limit of the quenching temperature or when the holding time is short. The carbides do not dissolve well and the solid solution concentration is low, so the hardness is often lower than the standard.

b) Second level. Martensite + a large amount of residual secondary carbides and primary carbides + a small amount of residual austenite This structure is formed at the lower limit of the quenching temperature or the temperature holding time is slightly shorter, the hardness is generally in the middle and lower limits of the qualified range of the standard.

c) Third level. Martensite + appropriate residual secondary carbides and primary carbides + a small amount of residual austenite The structure is formed at a suitable quenching temperature and temperature holding time.

d) Fourth level. Martensite + slightly residual secondary carbides and primary carbides + a small amount of residual austenite This structure is formed when the quenching temperature is slightly higher or the temperature holding time is slightly longer.

e) Fifth level. Martensite + a small amount of residual secondary carbides and primary carbides + a small amount of residual austenite This structure is formed when the quenching temperature is higher or the temperature holding time is longer, and it is the upper limit structure of the qualified quenching structure.

f) Sixth level. Martensite + residual secondary carbides and primary carbides + partially residual austenite + twin crystal carbide structure […]