RoHS Screening Analysis by EDX

Importance of the Topic

The restriction of hazardous substances (RoHS) in electronic and plastic products demands rapid and reliable screening methods to ensure compliance and protect human health and the environment. Energy dispersive X-ray fluorescence (EDXRF) offers non-destructive, multi-element analysis suitable for high-throughput RoHS screening in manufacturing, quality control, and regulatory laboratories.

Study Objectives and Overview

This application note evaluates Shimadzu’s EDX-7200 spectrometer equipped with PCEDX-Navi software for RoHS screening. Key goals include verifying improved sensitivity, reducing analysis time via an automatic time-reduction function, and demonstrating user-friendly operation without the need for custom calibration curve preparation.

Methodology and Instrumentation

Instrument configuration:

• EDX-7200 spectrometer with SDD detector and Rh X-ray tube
• PCEDX-Navi software for automated operation flow
• Pre-loaded calibration curves for plastics (PE, PVC), aluminum alloys, steels, copper alloys, tin alloys
• Screening conditions: 10–50 kV auto current, 10 mm collimator, primary filters #1–#4, atmospheric air, 100 s integration

Operation flow:

• Sample placement and condition selection
• Preliminary 15 s measurement for material identification
• Automatic calibration curve selection
• RoHS screening and pass/fail evaluation
• Report generation in Excel or HTML

Main Results and Discussion

Time reduction:

• Plastic sample measurement time reduced from 400 s to 51 s using automatic time-reduction
• Steel bolt screening time reduced from 300 s to 133 s

Detection limits:

• Improved lower limits of detection for Cd, Pb, Cr, Hg, Br, Cl, Sb compared with previous EDX models (e.g., 2 ppm Cd in PE, 0.5 ppm Pb in PE)

Repeatability:

• C-H-B-F-5-124HJ LDPE standard showed coefficients of variation below 1.5 % for all regulated elements

Practical Benefits and Applications

• Streamlined workflow from measurement to reporting enables non-specialist operators to perform RoHS screening
• Pre-loaded calibration curves eliminate the need for standard sample preparation
• Automatic time-reduction function increases sample throughput in QA/QC and manufacturing lines

Future Trends and Applications

Integration of EDXRF with laboratory information management systems (LIMS), expanded calibration libraries for emerging materials, and the adoption of machine learning algorithms for spectral deconvolution promise further improvements in accuracy, speed, and user autonomy. Miniaturized and portable EDXRF units could extend on-site screening in field and recycling applications.

Conclusion

The Shimadzu EDX-7200 with PCEDX-Navi software delivers significant enhancements for RoHS screening through faster analysis, lower detection limits, and simplified operation. Its automatic material identification, calibration curve selection, and time-reduction features make it an effective tool for regulatory compliance and high-throughput quality control.

References

• Application News Nos. X224, X225, X226, X227 (Shimadzu)