GB/T 40407-2021 in English
VALIDX-ray powder diffraction analysis method for determining the phases in portland cement clinker
- Issued on:2021-08-20
- Implemented on:2022-03-01
- File Format:PDF
- Delivery:Via email within 1~3 business days
$214.00
《GB/T 40407-2021硅酸盐水泥熟料矿相X射线衍射分析方法》由TC184(全国水泥标准化技术委员会)归口,主管部门为中国建筑材料联合会。
Introduction
Technical background and evolution of the standard
This standard is the first special analysis method standard for silicate cement clinker established in my country, which solves the technical bottleneck that traditional chemical analysis methods cannot distinguish isomorphous and heteromorphic crystals. After ISO released the "Cement Test Methods - Quantitative X-ray Diffraction Analysis" in 2008, my country carried out a 13-year method verification based on the Rietveld full spectrum fitting technology, and finally formed this standard.
Analysis of core analysis methods
| Analysis dimension | Traditional method | This standard method |
|---|---|---|
| Resolution | Single peak analysis (0.5° step width) | Full spectrum fitting (0.02° step width) |
| Accuracy | Relative error ≥15% | Alite phase error ≤3% |
| Applicable phase | Main crystal phase | Can distinguish M1/M3 crystal forms of C3S |
Typical Application Cases
A cement plant found abnormal belite content when testing clinker with a Rigaku SmartLab diffractometer. Through the Rietveld refinement of Clause 6.6 of this standard, it was found that it was caused by the conversion of β-C2S to γ-C2S. After adjusting the calcination system, the 28-day strength was increased by 4MPa.
Key Implementation Points
- Instrument calibration cycle: The goniometer angle must be calibrated with silicon powder standard material every 6 months, and calibration is required immediately after replacing the X-ray tube
- Sample preparation: When the powder is ground to less than 45μm, the preferred orientation error can be controlled within 2%
- Data validity: Rwp<8% and the range of three parallel measurements meets the requirements of Table 1
Radiation Safety Management
The standard places special emphasis on radiation protection of the diffractometer, and requires:
- Workplace dose rate ≤2.5μSv/h
- Be filter must be installed on the X-ray tube window
- Emergency stop button response time <0.5 seconds
Technology Development Outlook
With the application of synchrotron radiation light sources, the detection limit may be increased from the current 1% to 0.1% in the future, and real-time monitoring of the free state of CaO can be achieved. This standard lays the foundation for subsequent high-precision analysis methods.

Loading PDF document...
Error loading PDF. Please make sure the file is valid and try again.
We also recommend
-

GB/T 34615-2017 in English
Determination of combustion characteristics of CMSW for coprocessing in cement kiln
2017-10-14 -

GB/T 41060-2021 in English
Test method for determining frost resistance of cement mortar
2021-12-31