Titanium
transition metalProperties
| Property | Value |
|---|---|
| Atomic Mass | 47.867 amu |
| Category | transition metal |
| Group | 4 |
| Period | 4 |
| Electron Configuration | 1s2 2s2 2p6 3s2 3p6 3d2 4s2 |
| Electronegativity | 1.54 (Pauling) |
| Oxidation States | 4, 3, 2 |
| Melting Point | 1941 K (1667.8 °C) |
| Boiling Point | 3560 K (3286.8 °C) |
| Density | 4.506 g/cm³ |
| Discovered By | William Gregor (1791) |
About Titanium
Titanium is the ninth most common element in the crust but barely existed as a metal until Kroll worked out his 1940 process — reduce TiCl₄ with molten magnesium under argon, then vacuum-distill the MgCl₂ off a porous sponge. Every step is energy-hungry, which is why Ti still costs roughly 30× more than steel per kilogram. What you buy is an HCP α phase below 882 °C and a BCC β phase above, and the whole alloy-design game (Ti-6Al-4V, Ti-6242, β-21S) is about freezing in a two-phase microstructure that gives you steel-grade strength at 60% of steel's density. The other thing Ti does well is grow a 3–5 nm passive TiO₂ film instantly when it sees oxygen — that's why a hip stem can sit in saline forever, why a Ti reactor handles wet chlorine that would eat stainless, and why surgeons trust dental implants to osseointegrate. The other 95% of mined ilmenite and rutile never becomes metal at all; it ends up as the white TiO₂ pigment in everything from paint to toothpaste.
Fun Fact
The SR-71 Blackbird, the fastest jet aircraft ever built, had 93% of its structural weight made from titanium — and during the Cold War, the CIA had to secretly purchase the titanium from the Soviet Union through front companies to build the spy plane designed to fly over Soviet territory.
Common Uses
- Ti-6Al-4V forgings for compressor blades, airframes, and titanium golf heads
- Cementless hip and knee stems plus dental root-form implants that osseointegrate
- TiO₂ rutile pigment giving white paint, paper, and sunscreen its opacity
- Plate heat exchangers in seawater desalination and offshore platform piping
- Pulled-tube condensers in coastal power-plant cooling against chloride pitting
- Grade-2 CP titanium reactors for wet Cl₂, ClO₂, and HNO₃ chemical service