Boron
A hard metalloid element used in minute additions for press-hardenable boron steels, as a glass former, and as a constituent of NdFeB permanent magnets (boron in the Nd2Fe14B phase). Critical hardenability enabler for automotive hot-stamped structures.
Overview
Boron (symbol B, atomic number 5) is a hard, brittle metalloid with crystalline density around 2.34 g/cm³ and a melting point near 2076°C. In automotive steelmaking, additions of only ~10–50 ppm boron dramatically raise hardenability of manganese-chromium grades such as 22MnB5, enabling press-hardened steels (PHS) that achieve ~1500 MPa after hot stamping for B-pillars, door rings, bumper beams and other crash structures. Beyond steel, boron is a glass network former in automotive glazing and fibre insulation, a dopant in semiconductors, and an essential constituent of the Nd2Fe14B intermetallic phase that underpins NdFeB traction-motor magnets. Hexagonal boron nitride and boron carbide appear in specialty thermal and wear applications. Turkey, the United States and Chile dominate borate mineral supply. Although boron itself is relatively abundant versus heavy rare earths, its irreplaceable role in PHS and permanent magnets makes secure borate and ferroboron supply chain-relevant for EV and lightweight-vehicle programmes.
Automotive Applications
Similar Materials
Ferrochrome
Ferroalloy
An essential ferroalloy composed of chromium and iron used primarily as an alloying agent in the production of stainless and heat-resistant steels.
Ferrosilicon
Ferroalloy
An alloy of iron and silicon used primarily as a deoxidizer and alloying element in the production of steel and cast iron.
Molybdenum
Transition Metal
A refractory transition metal used primarily as an alloying addition in HSLA, multiphase and press-hardenable steels, and as a catalyst precursor. EU critical raw material with major supply from Chile, China and the USA.
Scandium
Rare Earth Element
A light rare-earth / transition metal used in Al-Sc alloys for high-strength lightweight structures and increasingly in additive manufacturing. Supply is limited and concentrated in China, Russia and emerging Australian projects.
Properties
Category
Type
Metalloid/Element
Available Colors
Available Forms
Key Properties
- Extreme hardenability boost at 10–50 ppm in steel
- Essential constituent of Nd2Fe14B magnet phase
- Hard, brittle metalloid / ceramic-like behaviour
- Glass network former (borosilicates)
- High melting point (~2076°C)
- Low density among structural-relevant elements
Technical Specifications
Density
2.34 g/cm³ (crystalline)
Tensile Strength
Not used as a bulk structural metal; enables ~1500 MPa PHS grades via hardenability
Temperature Resistance
Melts at ~2076°C; PHS hot-stamping austenitisation typically ~900–950°C; magnet and glass uses per system design
Sustainability
Sustainability Rating
Boron in steel scrap is retained in remelt but at ppm levels is not separately recovered. Borate mining (notably Turkey) has moderate environmental footprint relative to many critical metals; magnet-route boron is bound in NdFeB and recovered only when magnet recycling loops mature. Substitution for PHS hardenability is limited without redesigning alloy and process windows.