QC/T 262-2025 (QC/T 262-1999) PDF EnglishUS$170.00 · In stock · Download in 9 seconds
QC/T 262-1999: Metallographic Test of Car Carburizing Gear Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See step-by-step procedure QC/T 262: Historical versions
QC/T 262-1999: Metallographic Test of Car Carburizing Gear---This is an excerpt. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.), auto-downloaded/delivered in 9 seconds, can be purchased online: https://www.ChineseStandard.net/PDF.aspx/QCT262-1999QC AUTOMOTIVE INDUSTRY STANDARD OF THE PEOPLE’S REPUBLIC OF CHINA Replacing ZB T04 001-88 Metallographic Test of Car Carburizing Gear APPROVED ON. MARCH 15, 1999 Implemented on: MARCH 15, 1999 Approved by. State Bureau of Machine Building Industry Table of Contents1 Theme Contents and Applicable Scope . 3 2 Normative References . 3 3 Terms .. 3 4 Specimen Requirements . 4 5 Technical Requirements .. 4 6 Structure Levels . 4 Additional Information... 10 Metallographic Test of Car Carburizing Gear1 Theme Contents and Applicable Scope1.1 This Standard specifies the definitions and test methods of metallographic structure, effective layer depth of carburized case for the car steel carburizing gear. 1.2 This Standard is applicable to the car gear with effective depth of carburized and hardened case greater than 0.3mm. 1.3 This Standard is applicable to the quality inspection of gear after finishing all the heat treatment procedures.2 Normative ReferencesGB/T 9450 Steels - Determination and Verification of the Depth of Carburized and Hardened Cases GB/T 8539 General Specification for Quality Inspection of Gear Materials and Their Heat Treatment3 Terms3.1 Surface hardness The surface hardness near the pitch circle in the center of tooth-width. 3.2 Center hardness The hardness, on the cross-section in the center of tooth-width, and on the intersecting position between tooth centerline and tooth root circle (see Schematic diagram). 3.3 Effective depth of carburized and hardened case From the tooth surface, the vertical distance under 9.81N (1kgf) load measured to 550HV, or under 49.03N (5kgf) load measured to 515HV.4 Specimen Requirements4.1 When preparing the specimen, no phenomenon such as the structure changes due to heat shall occur. 4.2 When measuring the effective depth of carburized and hardened case, the tested surface shall be parallel to the working stage of hardness machine.5 Technical Requirements5.1 The effective depth of carburized and hardened case shall abide by the product drawing, and be subject to the tooth root and pitch circle positions; while its test method shall conform to the provisions of GB/T 9450; the decrease to the center hardness shall conform to the provisions of GB/T 8539. 5.2 The carbon content on the surface course is recommended to be 0.8%~1.0%. 5.3 Carbide Inspect under the magnification of 400×; the inspection position shall be subject to the addendum angle and working surface; evaluate as per the carbide level diagram in this Standard. The constantly meshed gear is qualified for Level 1~Level 5; while shifting gear is qualified for Level 1~Level 4. 5.4 Residual austenite and martensite Inspect under the magnification of 400×; the inspection position shall be subject to surface near pitch circle and tooth root; separately evaluate as per the residual austenite and martensite level diagram; it is qualified for Level 1~Level 5. 5.5 Surface hardness is HRC 58~63, the center hardness shall be specified by the product drawing. 5.6 If the surface is not martensite structure; the maximum depth shall not exceed 0.02mm.6 Structure Levels6.1 The carbide levels shall be determined as per its shape, quantity, size, distribution ......Source: Above contents are excerpted from the full-copy PDF -- translated/reviewed by: www.ChineseStandard.net / Wayne Zheng et al. |
