PREVIOUSLY ASKED IN:
PSC Miscellaneous Prelims 2018
Answer
Hafnium Carbide (HfC)
Explanation
Hafnium carbide (HfC) and Tantalum carbide (TaC) are recognized as the world's most heat-resistant materials. Recent research around 2016-17 confirmed that Hafnium carbide has the highest melting point of any known material, exceeding 3,900 degrees Celsius (approx 3,958 °C). Due to this extreme refractoriness, it is highly suitable for use in extreme environments like thermal protection systems for spacecraft and jet engines.
Key Points
- > Hafnium carbide (HfC) has a melting point of around 3,958 °C.
- > It belongs to a class of materials known as ultra-high temperature ceramics (UHTCs).
- > It is crucial for building heat shields for spacecraft re-entering the Earth's atmosphere.
- > Among pure metals, Tungsten (W) has the highest melting point at 3,422 °C.
- > Diamond (a carbon allotrope) also has a very high melting point of about 3,550 °C.
- > Titanium is strong and light but its melting point is only around 1,668 °C, much lower than HfC.
Additional Information
Melting Points of High Heat Materials
| Material | Melting Point (Approx) | Common Application |
|---|---|---|
| Hafnium Carbide (HfC) | 3958 °C | Spacecraft thermal shields |
| Tungsten (W) | 3422 °C | Lightbulb filaments |
| Titanium (Ti) | 1668 °C | Aerospace frames |
| Iron (Fe) | 1538 °C | Construction and steel making |
Memory Tips
- Hafnium = Highest: Remember the 'H' in Hafnium stands for Highest melting point.