explain why diamond is used aexplain why diamond is used as an industrial cutting tools an industrial cutting tool

Diamond is widely used as an industrial cutting tool, mainly based on its extreme physical and chemical properties, which give it irreplaceable advantages in processing superhard materials and high-precision machining.

 

Here is a detailed explanation:

1. Extremely high hardness (the core reason)

• Mohs hardness level 10: Diamond is the hardest substance known in nature, with carbon atoms in its crystal structure forming a three-dimensional network structure through covalent bonds, making it easy to cut other materials (including hard alloys, ceramics, glass, etc.).
• Application scenario: Used for processing superhard materials that are difficult to cut with traditional tools, such as tungsten carbide, zirconia ceramics, granite, etc.

 

2. Excellent wear resistance

• The wear rate of diamond is much lower than that of tool materials such as hard alloys and ceramics, and its lifespan can be increased by tens to hundreds of times, reducing the frequency of downtime and tool changes, making it suitable for large-scale and efficient production.

 

3. High thermal conductivity

• The thermal conductivity is extremely strong (about 1000-2000 W/m · K), which can quickly dissipate the heat from the cutting area, avoiding thermal deformation of the workpiece and thermal damage to the tool, especially suitable for high-speed machining.

 

4. Low friction coefficient

• Smooth surface with low friction coefficient, reducing cutting resistance, lowering energy consumption, and improving the surface smoothness of the workpiece (up to mirror effect).

 

5. Chemical stability and accuracy

• Resistant to acid and alkali corrosion at room temperature, but it should be noted that chemical reactions may occur with iron-based metals (iron, nickel, cobalt) at high temperatures (>700 ℃), making it unsuitable for processing ferrous metals (such as steel and cast iron).
• The cutting edge can be ground to nanometer level sharpness, suitable for micrometer level ultra precision machining (such as optical lenses, semiconductor components).

 

 

Limitations and coping strategies

 

1. Brittleness: Diamond has poor toughness and is prone to chipping, making it unsuitable for intermittent cutting or impact loads.
2. High temperature oxidation: Heating to above 800 ℃ in air will cause oxidation or graphitization, and the cutting temperature needs to be controlled.
3. Iron group metal reaction: cubic boron nitride (CBN) is commonly used as a substitute in processing steel parts.
4. High cost: Natural diamond tools are expensive, and artificial polycrystalline diamond (PCD) or chemical vapor deposition (CVD) diamond coatings are commonly used in industry to reduce costs.

 

Typical industrial application scenarios

1. Precision machining of non-ferrous metals: High smoothness cutting of aerospace components such as aluminum, copper, and titanium alloys.

2. Processing of non-metallic hard materials: cutting and polishing of stone, concrete, and carbon fiber composite materials.
3. Precision manufacturing industry: semiconductor silicon wafer cutting, optical glass engraving.
4. Petroleum drilling: PCD drill bits are used for geological exploration.

 

summary
Diamond, with its three core advantages of hardness, wear resistance, and thermal conductivity, has become the "ultimate tool" in the field of industrial cutting, especially irreplaceable in precision machining and superhard material processing. However, its application requires a combination of material properties (avoiding iron group metals) and processing conditions (avoiding impact), and the use of synthesis technology to reduce costs and expand industrial applicability.