Niobium crystals subsequent to an anodized dice of 99.95 p.c pure niobium. (Alchemist-hp/Wiki Commons/)
A chunk by Ron Lieback that appeared not too long ago on the Cycle World web site introduced that “The Hollister, California-based bike firm [Lightning] is betting on new niobium expertise…
“A yet-to-be-named electrical bike prototype is below approach that may leverage the metallic niobium. Lightning Bikes says the initiative intends to innovate and take a look at the metallic in varied car elements, which is able to enhance its efficiency and, ultimately, assist the bike exceed the 250-mph mark.”
I needed to know extra about how niobium may assist, and have since realized some fascinating issues.
What Niobium Is, and What It Does
Niobium, which was at one time known as columbium, isn’t a lightweight metallic. At a density of 8.57 grams per cubic centimeter, it’s heavier than iron (7.87); however its largest utility takes the type of ferroniobium, a mixture with iron that allows simple alloying with round 1/10 of a p.c of niobium, leading to high-strength, low-alloy (HSLA) steels extensively utilized in auto our bodies and constructions. HSLA steels save weight as a result of better power makes it attainable to make use of much less materials. There are far stronger specialty metal alloys out there, however their excessive prices makes them unattractive for auto building.
CBMM, the Brazilian niobium producer named within the article, ships hundreds of tons of ferroniobium and niobium oxide yearly; extra on them shortly. The present value of niobium is within the vary of $18–$20 per pound.
On this utility, niobium strengthens metal simply as vanadium did for Henry Ford’s Mannequin T: by means of a mechanism known as grain-boundary hardening. Metals are crystalline, that means their atoms naturally prepare themselves into orderly ranks and rows. However metallic objects typically are polycrystalline, that means they include a jumble of myriad tiny crystals that are oriented randomly and separated by intergranular areas through which crystalline order isn’t current.
How Niobium Works
Below excessive stress, metallic crystals yield throughout one row of atoms at a time as native defects, factors of weak point known as dislocations, propagate by means of them. However when shifting dislocations arrive at a grain boundary, they encounter chaotic and extremely strained areas that impede their progress. The extra such grain boundaries a fabric comprises, the extra strongly it resists deformation. This is the reason fine-grained supplies are usually stronger than their coarse-grained counterparts. When added to metal in very small quantities, grain refiners akin to vanadium, niobium, tantalum, and titanium all act to nucleate the formation of very nice numbers of crystals because the molten metallic begins to solidify. The ensuing metal could be finer-grained and due to this fact stronger.
When added to stainless steels, niobium affords one other benefit: It may well assist stop the dreaded intergranular corrosion. This happens when carbon atoms diffuse into the intergranular zones and mix with close by chromium, a needed constituent of stainless; this depletes the chromium from adjoining metallic crystals and makes them weak to intergranular corrosion. Including a little bit of niobium, which mixes with carbon to type niobium carbide, can stop chromium depletion and, in flip, such corrosion.
Niobium additionally finds use within the preparation of high-temperature refractory metals to be used in fuel generators.
The Electrical Connection
Since HSLA steels are already extensively used within the auto trade, it appeared unlikely to me that they’d function a foundation for supporting a Bonneville speed-record try. There needed to be extra to the story—one thing new.
And there may be. Niobium has a brand new function within the manufacturing of lithium-ion batteries. In Japan, Toshiba has, for a while now, produced so-called “LTO” (lithium titanium oxide) anodes as an necessary ingredient in its Tremendous Cost ion Battery (SCiB). Toshiba claims the SCiB is able to 20,000 charge-discharge cycles, and of being rechargeable to 80 p.c of full capability in six minutes. The corporate additionally claims the battery retains 71 p.c of its room-temperature discharge capability at -22 levels Fahrenheit.
Extra Sturdy Anodes
When a lithium-ion battery makes use of the standard carbon-anode building, the inflow and outflux of lithium ions throughout charge-discharge causes the anode to cyclically swell. This ultimately causes conductive flakes to detach from it, a serious drawback. Further-fast charging accelerates this, resulting in the graphite anode being plated with lithium metallic. LTO is alleged to keep away from this, and now Toshiba has taken a further step in creating an NTO, or Niobium Titanium Oxide anode, stated to significantly enhance vitality storage per unit of quantity.
A skinny coating that replaces the separator usually needed between cathode and anode additional reduces the Toshiba NTO-anode li-ion battery’s quantity.
Now we’re talkin’! A denser, lighter li-ion battery would certainly be helpful for anybody looking for an electrical bike pace report.
Brazil provides a majority share of the world niobium market, and reserves close to Araxá held by CBMM (Companhia Brasileira de Metalurgia e Mineração) are reportedly giant sufficient to produce current world demand for 500 years! In 2011 a Chinese language group took a 15-percent stake in CBMM, and a bunch of 4 Japanese and two South Korean corporations purchased one other 15 p.c, leaving the billionaire Moreira Salles household firmly in management with 70 p.c. Are you able to say “globalization”?
In trying a pace report at Bonneville, it will seem that CBMM and its Asian companions search to publicize niobium’s increasing capabilities.