Overview
This document outlines the chemical composition requirements for tantalum and tantalum alloys as specified by ASTM standards (B365, B708). It covers both finished products and ingots, ensuring material consistency for critical applications in electronics, aerospace, and high – performance industries.
Chemical Requirements for Finished Products
| Element | Electron – Beam Cast (R05200) Unalloyed Tantalum | Sintered (R05400) Unalloyed Tantalum | Electron – Beam Cast (R05255) 90% Tantalum 10% Tungsten | Electron – Beam Cast (R05252) 97% Tantalum 2.5% Tungsten | Electron – Beam Cast (R05240) 60% Tantalum 40% Niobium |
| O | 0.025 | 0.035 | 0.025 | 0.025 | 0.025 |
| N | 0.010 | 0.010 | 0.010 | 0.010 | 0.010 |
| C | 0.0015 | 0.0015 | 0.0015 | 0.0015 | 0.0015 |
| H | 0.020 | 0.020 | 0.020 | 0.020 | 0.020 |
Chemical Requirements for Tantalum and Tantalum Alloy Ingots
| Element | Electron Beam Cast (R05200) Unalloyed Ta | Sintered (R05400) Unalloyed Ta | Electron Beam Cast (R05255) 90% Ta 10% W | Electron Beam Cast (R05252) 97.5% Ta 2.5% W | Electron Beam Cast (R05240) 60% Ta 40% Nb |
| C | 0.010 | 0.010 | 0.010 | 0.010 | 0.010 |
| O | 0.010 | 0.030 | 0.010 | 0.010 | 0.020 |
| N | 0.010 | 0.010 | 0.010 | 0.010 | 0.010 |
| H | 0.0015 | 0.0015 | 0.0015 | 0.0015 | 0.0015 |
| Nb | 0.100 | 0.100 | 0.100 | 0.500 | 35.0 – 42.0 |
| Fe | 0.010 | 0.010 | 0.10 | 0.010 | 0.010 |
| Ti | 0.010 | 0.010 | 0.10 | 0.010 | 0.010 |
| W | 0.050 | 0.050 | 9.0 – 11.0 | 2.0 – 3.5 | 0.050 |
| Mo | 0.020 | 0.020 | 0.020 | 0.020 | 0.020 |
| Si | 0.005 | 0.005 | 0.005 | 0.005 | 0.005 |
| Ni | 0.010 | 0.010 | 0.010 | 0.010 | 0.010 |
| Ta | remainder | remainder | remainder | remainder | remainder |
Key Significance
- Standard Compliance: Meets ASTM B365, B708, and B521 requirements, ensuring material quality for industrial use.
- Alloy Customization: Different grades (e.g., 90% Ta – 10% W, 60% Ta – 40% Nb) support specialized applications like high – temperature coatings and electronic components.
- Impurity Control: Strict limits on O, N, C, H ensure tantalum performance in critical environments (e.g., vacuum systems, aerospace).
Application Guidance
- Aerospace: Alloys like 90% Ta – 10% W (high – temperature resistance) suit engine parts.
- Electronics: Unalloyed tantalum (low impurities) is ideal for sputtering targets and capacitors.
- Quality Assurance: Certifiable per ASTM standards, providing traceability for regulated industries.
Document Value
Essential for manufacturers, suppliers, and engineers to verify tantalum alloy chemistry, ensuring product reliability and regulatory compliance. Use this to select materials, validate specifications, and support technical documentation.