The process of making a Kikusumi ceramic knife involves 9 key stages before the finished knife emerges complete. Along the way there are multiple quality inspections made to ensure each knife meets the high standards we expect.
- Dry Pressing
- Cold Isostatic Pressing
- High Temperature Sintering
- Low Temperature Sintering for Kikusumi Logo
- Handle Injection
- Blade Grinding
- Blade Sharpening
- Blade Polishing
- Luxury Gift Packaging
CERAMIC KNIFE PROCESS
1. DRY PRESSING
The process of making a Kikusumi Ceramic Knife begins with the selection of sub-nanometer zirconium oxide powder #4 which is 30% finer than the #2 powder inferior ceramic knives are made of. Zirconium is an advanced, high-tech ceramic material that is second only to diamond in hardness. The first step in making Kikusumi knives is to first put the Zirconia powder into a mould. Next, about 200 tons of pressure is applied to the moulded powder with hi-tech forging machines. Kikusumi uses no adhesives during this lengthy process and this results in 30% lower blade porosity. Once complete, the basic shape of the ceramic blade has been formed.
2. COLD ISOSTATIC PRESSING
During the second-stage process the pressed blades are inserted into a tied PVC vacuum bag and then placed into a closed container. An oil and water mixture is added and then over 200 mpa of pressure is applied for a lengthy period of time. The process is called Cold Isostatic Pressing and makes the blades both denser and more durable. After this process the blade size is 10% smaller and very dense.
3. HIGH TEMPERATURE SINTERING
For the third stage, one of the most high-tech sintering machine with Intelligent temperature control system which can keep the temperature controlled at +-1°C. It can make the blades been more heat evenly, Blades made this way have higher density, lower porosity and lower deformation.
4. LOW TEMPERATURE SINTERING
For the fourth stage, the iconic Kikusumi logo is applied to the blades and a lower temperature sintering is applied, The extra firing has a two-fold effect – the blade gains extra durability and the warm glow of the Kikusumi design comes to life.
5. HANDLE INJECTION
Kikusumi knife handles are attached to each ceramic blade by using and advanced injection molding process which is both stronger and more sanitary than using the glue and thermal bonding that many manufacturers use. The result is a knife with a stronger structure and superior hygienic properties.
6. BLADE GRINDING
The process of grinding and polishing the surface of the ceramic blade is composed of three steps. Blades are first flat grinded on both sides of the blade with a diamond wheel. Two kinds of flat grinding: coarse grinding, accurate grinding. The former is speedy and high efficiency. The latter, after the coarse grinding is finished, can gloss surface of ceramic blade. B.Around Grinding: Grinding the edges of the blades. C.Open Edge: Produce the edge preliminarily.
7. BLADE SHARPENING
Depending on the knife model, the blade edge is sharpened to a 11°-13° angle and the tip edge within a range of 35°-42°.
8. BLADE POLISHING
Every KIikusumi ceramic knife blade is polished by hand to achieve maximum sharpness. There are three steps to the polishing process:
- Coarse Flat Grinding consists of polishing both sides of each ceramic blade with a diamond-dust This is a relatively fast and time-efficient process.
- Precision Flat Grinding the edges of the blades comes after the coarse grinding is finished. This is a slow and time-consuming process that results in a high-gloss surface on each ceramic blade.
- Open Edge Polishing produces the final refinement to the blade’s edge that is complete when the ideal sharpness is achieved.
At the final stage every knife is sanitized with vegetable detergent and a final inspection of the entire knife is conducted to ensure Kikusumi Knife standards of quality are met.
10. LUXURY GIFT PACKAGING
Great thought and meticulous planning lies behind our gift boxes. As each gift box that is opened we wanted to make that singular moment of discovery as exciting as possible. The unique story of Kikusumi knives is revealed in several stages throughout the process that is intended to add emotion and convey the passion we put into our products. A black and white graphic representing actual Kikusumi charcoal provides the backdrop to the gift box top. Above it in shimmering “sumi” black is an outline of our ceramic knives along with a glowing red “kiku” flower.