陶瓷刀工艺

现在的陶瓷刀片生产工艺方法采用的是气氛保护烧结(GPS)+热等静压处理(HIP)方法，其生产工

艺的主要流程如下：

混合配料→压制→排胶→气氛保护烧结→无包套热等静压处理→高精度刃磨→试刀→包装检验。

1、混合配料：本工序的目的是使各种原料充分均匀混合。粉料处理工艺为：球磨→振磨→球磨→加胶→球磨。

2、坯体压制：陶瓷刀片的干粉压制工序对粉体形貌、粉体表面电荷状况以及混合粉体的造粒要

求都很高，故压制工艺难度较大。

3、坯体排胶：陶瓷刀片的脱胶工艺与硬质合金刀具生产工艺相似。

4、GPS+HIP处理：烧结工艺采用气氛保护烧结(GPS)+热等静压(HIP)处理技术。

5、刀片刃磨：陶瓷刀片的刃磨质量对刀具使用性能影响很大。

6、试刀：对于不同批次、不同时间生产的陶瓷刀片，除监控其性能指标外，在出厂前还应进行

试刀，以检验刀片的切削性能。试刀一般在工厂的机床上完成。

7、包装检验：检查产品中的破损、残品，次品，合格，包装。

A ceramic knife is a knife made out of very hard and tough ceramic, often

; also known as zirconia). These knives are usually zirconium oxide (ZrO

2

produced by dry pressing zirconia powder and firing them through

solid-state sintering. The resultant blade is sharpened by grinding the edges with a diamond-dust-coated grinding wheel. Zirconia ranks 8.5 on the Mohs scale of mineral hardness, compared to 6 to 6.5 for hardened steel, and 10 for diamond. This very hard edge rarely needs sharpening. Zirconium oxide is used due to its polymorphism. It exists in three phases: monoclinic, tetragonal, and cubic. Cooling to the monoclinic phase after sintering causes a large volume change, which often causes stress fractures in pure zirconia. Additives such as magnesium, calcium and yttrium are utilized in the manufacture of the knife material to stabilize the high-temperature phases and minimize this volume change. The highest strength and toughness is produced by the addition of 3 mol% yttrium oxide yielding partially stabilized zirconia. This material consists of a mixture of tetragonal and cubic phases with a bending strength of nearly 1200 MPa. Small cracks allow phase transformations to occur, which essentially close the cracks and prevent catastrophic failure, resulting in a relatively tough ceramic material, sometimes known as TTZ (transformation toughened zirconia).

Ceramic knives will not corrode in harsh environments, making them popular with scuba divers. They are also nonmagnetic and do not conduct electricity, which can be useful during bomb disposal operations. Their chemical inertness to extreme pHs, and their ability to retain a cutting edge longer than forged metal knives make them a suitable culinary tool for slicing boneless meat, vegetables and fruit. Since they are brittle

they may break if dropped on a hard surface, and cannot be used for chopping through bones or frozen foods, or in other applications which require prying, which may result in chipping or catastrophic failure. Several brands now offer a black colored blade made through an additional hot isostatic pressing (HIP) step, which improves the toughness.

Ceramic knives may present a security problem as ceramics are not seen by conventional metal detectors. To hinder misuse of concealed knives many manufacturers include some metal to ensure that they are seen by standard

equipment. Ceramic knives can be detected by extremely high frequency scanners (limeter wave scanners) and X-ray backscatter scanners