This IS NOT a Bio-Chem Journal Post


Hi people! ;D
Yesterday I was walking around Causeway Point, when I went to Metro, and saw this thingy on promotion.



Its a knife, made of ceramic. According to the promoter, she says the knife can absorb some smell (like the 'spicy' smell of onions) and keep flavours inside food you cut. Also, she cut a ginger and let me smell the knife, which I did, and I didn't smell anything, nor see any stains on the knife, and the ginger was still as nice and fragrant. It was so nice too, the design, white blade, and it seems like its blunt, but actual fact, it can cut raw carrot without using any energy (YES! I've tried it). So I was convinced that I wanted to buy, until I saw the price, $100 for a knife, I thought it was too expensive, so I decided not to. However, I did take a broucher home and take a look at it, and I saw this.



It reads...


WARRANTY
All Kyocera ceramic products are warranted to be free from defects in material and workmanship for (5) years after the original purchase date. Please refer to the Kyocera packaging insert for details.

RE-SHARPENING
Made from zirconium oxide, a material close in hardness to diamond, our ceramic blades actually require diamond wheels to be re-sharpened. Depending on use, ceramic knives will require sharpening about 1/10th as often as steel knives.


So I saw that, zirconium oxide, a material close in hardness to diamond, and was wondering, that's cool. A material that is so hard, it will not roll, or slide like steel blades, has better edge retention, will not rust, not change colour, impervious to acids, juices, oils, salts or other elements, and lighter then steel blades. So I decided to do a little research on the material, and here's what I got.

So zirconium oxide can whistand temperature up to 2400°C and it has a high density. It has a high hardness, and high fracture toughness. It does not conduct heat, nor electricity (unless above 600°C). Also, it is immune to chemicals, which makes it immune to molten metal and it wears resistance.

Pure zirconium oxide exists in 3 different structures at different temperature. It has a cubic structure when above 2370°C. At 1170°C to 2370°C, it has a tetragonal structure. At low temperature, below 1170°C, it has a monoclinic structure. It can transform from a tetragonal structure to a monoclinic structure rapidly, however, it has a 3% to 5% volume change, causing it to crack extensively, making it useless for any mechanical or physical use. Hence, chemicals are added when cooling or heating zirconium oxide, chemicals like MgO (Magnesium oxide), CaO (Calcium oxide) Y2O3 (Yttrium oxide). With the correct amount of chemicals added, it can retain its cubic form when in room temperature, making it extremely sturdy and good for uses, as it does not go through the destructive phase of heating and cooling.

Okay. That's the summarized version. And I found out something, my initials, TZP, is a name of a microstructure called, tetragonal zirconia polycrystal! ;D

References

Link One

Glossary
Fracture toughness
The ability for a material to whistand a fracture with a crack in it.

Molten metal
Metals that are in a liquid form after high temperatures of melting.

Cubic
Resembling the shape of a cube.

Tetragonal
Resembling the shape of the 'selecting' arrow in Sims 3.

Monoclinic
A slanted cube.

;D Okay. End of report.
Loonaeklips blogged on 9:00 PM
© A Loonaeklips Post ;D