Quenchard: Superconducting Magnet Quench
Thermodynamics & Statistical Physics arc, page 71 of 193. Back to The Pixelated Physics Universe
Who they are
Quenchard has one line, and says it often: “One warm spot. everything goes normal.”
Quenchard is a character of the Thermodynamics & Statistical Physics arc: drawn in pixels, ruled by one piece of real physics, and never allowed to break it.
The physics
A superconducting magnet quenches when a local spot turns normal; Joule heating spreads the normal zone and the stored energy dumps. NbTi: Tc ≈ 9.2 K.
$$ \begin{gathered} T < T_c(B): \ \rho = 0, \qquad T_c(\text{NbTi}, B = 0) \approx 9.2\ \text{K} \\ E = \tfrac{1}{2} L I^{2} \end{gathered} $$
| Symbol | Meaning | SI unit |
|---|---|---|
| $T$ | conductor temperature | K |
| $T_c(B)$ | critical temperature at field B | K |
| $\rho$ | electrical resistivity | Ω·m |
| $E$ | stored magnetic energy dumped in a quench | J |
| $L$ | magnet inductance | H |
| $I$ | operating current | A |
Sources
- M. N. Wilson, Superconducting Magnets (Oxford, 1983)
Crossovers
Quenchard meets Cryo Fault (Ductile-to-Brittle Transition). Quenchard's magnet runs at liquid-helium temperatures, where Cryo Fault's warning matters: some steels turn brittle in the cold. Cryogenic structures use materials, such as austenitic stainless steel, that stay ductile.
Quenchard meets Remanenza (Magnetic Hysteresis Loop). Quenchard dumps a magnet's stored energy, ½LI², when a spot goes normal. Remanenza's hysteresis loss is quieter: each cycle of a magnetic material dissipates energy equal to the loop area.
Wear the lore
- Quenchard, the Superconducting Duke Mug
- Related infographic poster: Niobium's Mixed State – Plate 062 Physics Poster
Concept keywords: Superconducting Magnet Quench, Quenchard, Thermodynamics & Statistical Physics, physics lore, Pixelated Physics