Bulk Analysis of Tool Steels High Speed (T & M), Hot and Cold Work (H & D)

Importance of Topic

This application note addresses the chemical characterization of high-speed, hot-work and cold-work tool steels by glow discharge optical emission spectroscopy (GDOES). Accurate alloy analysis is essential for steel producers to control quality and cost, and for end users to ensure that tools meet performance requirements under demanding conditions.

Objectives and Study Overview

The study evaluates the performance of the LECO GDS500A spectrometer for bulk analysis of four tool steel types (T-1, M-1, H-13, D-2) against certified reference materials. Key aims include:

• Verifying chemical composition accuracy across multiple alloy grades.
• Demonstrating precision and repeatability of the method.
• Assessing analysis throughput and sample preparation requirements.

Methodology and Instrumentation

Tool steel samples were prepared by surface grinding with a 120-grit zirconia belt or wet polishing. The GDS500A uses a glow discharge source to sputter material from the sample surface and excite ground-state atom emission, simplifying spectra and reducing interferences common in high-alloy steels.

Used Instrumentation

• LECO GDS500A atomic emission spectrometer
• Belt Grinder (LECO BG) or Polisher (LECO VP) for sample prep

Main Results and Discussion

Analysis of certified standards for four tool steel families showed excellent agreement with reference values and low relative standard deviations (typically <2%). Key findings:

• T-1 steel (W-type): Carbon, chromium and tungsten matched certified values within 1–2% relative error; RSDs <1.7%.
• M-1 steel (Mo-type): Molybdenum measured with <0.4% relative error, overall precision <1% RSD.
• H-13 steel (hot-work): Major alloying elements (Cr, Mo, V) within 1% of certified concentrations; RSDs generally <1%.
• D-2 steel (cold-work): High chromium content (≈11%) determined with 0.8% relative error and <0.1% RSD.

Calibration curves for key elements (Mo, W) were linear over broad concentration ranges. The glow discharge approach minimized matrix effects and metallurgical history artifacts.

Benefits and Practical Applications

The GDS500A method offers:

• Rapid, accurate bulk composition analysis of diverse tool steel grades.
• Reduced sample handling since multiple burns can be performed at one location.
• Robust calibration and drift correction using certified and non-certified standards.
• Cost control through verification of incoming and in-process steel chemistry.

Future Trends and Potential Applications

Advances in glow discharge sources and detector electronics may further improve sensitivity for trace elements and expand analysis to coatings or thin layers. Integration with automated sample changers and enhanced software could enable higher throughput laboratories to screen larger batches of alloys. Customized calibration strategies using user-supplied reference materials will support niche steel grades and emerging high-performance alloys.

Conclusion

The LECO GDS500A demonstrates reliable performance for the bulk chemical analysis of tool steels, delivering accurate results with high precision and rapid analysis times. Its ability to handle multiple alloy grades with minimal matrix interferences makes it a valuable tool for both steel manufacturers and end-users.

Reference

LECO Corporation. Spectroscopy Performance Note: Bulk Analysis of Tool Steels by GDS500A, Form No. 209-076-032, June 2007.