Monocrystalline diamond tool design principle and the use of technology about the main points.

 

1. Monocrystalline diamond tool lens face processing mechanism

 

After cutting processing of the residual area of highly h = f / (CTGKR + CTGKR ‘) that is the theory of surface roughness has processing, it is with the feeding of f, cutting tools PianJiao kr and vice PianJiao Lord kr ‘decreasing of reduction. Due to the decrease of the Lord PianJiao kr can make Fy force increased rapidly and cause tool vibration, reduce feed f will affect cutting efficiency, so usually by reducing the vice PianJiao kr ‘to reduce the surface roughness.

 

Conventional cutting tool surface with a rough, flat blade bad property, if choose vice PianJiao too small, on the one hand, vice cutting edge smooth will not reflect the complex to already processing surface; On the other hand, we will aggravate the knife surface and after vice of the friction surface has processing, will be processed surface “hair”. So in conventional cutting, vice PianJiao about 2 ° minimum value when the surface roughness, further reduce PianJiao vice is already working surface quality deterioration.

 

Monocrystalline diamond tool surface roughness value may be less than Ra0.01? M, blade can achieve at least in quality 100 times a microscope without defect, and minimal friction coefficient, so the vice PianJiao limit can be reduced to 0 ~ 2 ‘, which can make the surface roughness close to the theoretical value or equal to zero, the actual surface roughness can achieve a mirror or the super-smooth surface requirements.

 

This shows, cutting tool itself, monocrystalline diamond tool lens face processing mechanism is through the tools of the surface is bright and clean and no defects vice cutting edge (the light blade) effect, make the surface roughness theoretical values close to zero for mirror surface treatment effect.

 

2 monocrystalline diamond tool design

 

Design monocrystalline diamond tools to consider the main factors are: (1) the precision requirement by processing components; (2) the actual processing conditions; (3) diamond material properties.

 

Design monocrystalline diamond tools, should follow the following principles: (1) because of monocrystalline diamond high hardness and high processing hard, so the shape of the cutting tools should be as simple as possible; (2) according to monocrystalline diamond brittleness is big, impact resistant ability is poor characteristic, should practical processing conditions, through to the cutter geometrical shape optimization to improve the force of impact resistant ability; (3) by processing parts according to the demand for the accuracy of the light blade length design, and should also consider the cutting tool cut thin ability.

 

Several common here in cutting tools as an example to discuss the design scheme of monocrystalline diamond tools.

 

The computer hard disk substrates lathe tools

 

The computer hard disk substrates for information storage, its material for aluminum or aluminum alloy, substrate surface roughness is lower, the storage density, thereby reducing the surface roughness value is the key. And because the substrate thickness is less than 0.9 mm, to prevent its deformation, should try to reduce the processing cutting force and extrusion.

 

Hard disk substrate by cutting with good stability and high precision of rigid disk lathe. Cutting depth about 0.01 ~ 0.02 mm, feeding about 0.5 mm.

 

Hard disk substrates monocrystalline diamond turning shape of shape as shown in figure 1 below. There are two main force of the cutting edges, the process can be controlled feed. The longer the light blade can guarantee or so two direction when processing the blade knife light after the wear not interfere with each other. The two main knife surface before in the next 5 ° direction out, so as to get about 2.5 ° of negative rake Angle, make scraps to surface processing flow, in order to avoid scraps scratch already processing surface. Diamond tools are very sharp blade arc radius of less than 100 nm, 5 ° Angle already can be fully after the smaller knife surface and surface processing of extrusion and has friction.

 

This tool is the key quality requirements in 500 times and the tip of blade microscope no defects. The design principle is also suitable for other super precision mirror processing cutting tool.

 

Jewelry sword of flowers

 

Jewelry batch of flower blade for in gold, silver jewelry in the form of milling leaves decorative pattern design, is actually a molding cutter, head of its shape as shown in figure 2 shows. Knife in the 110 ° pointed ~ 150 ° between, in order to adapt to the different size and the depth of the decorative pattern processing. Due to the group of flower machine structure is simple, rigid sent, vibration, together with the intermittent dry cutting, processing condition is very poor, so batch cutter knife to spend with strong impact resistant ability. 5 ° negative Angle and 1 before ° ~ 1.5 ° Angle can effectively increase the intensity of the blade, and the smaller the still can make the cutting tool and workpiece squeezed between appropriate by, the cutting not “FaXu”, prevent cutting vibration in the already processing surface formation “chatter marks”.

 

Jewelry sword and processing of flowers and some specular adornment watchcase of parts of the cutting tool design principles with roughly the same, and the tools required in 200 ~ 500 times the blade microscope mouth no collapse.

 

Contact lenses lathe tools

 

Contact lenses USES the material is very soft, and a certain tensile strength, general material cutting tools due to excessive circular blade, it is hard to the cutting processing. Because after turning processing and a grinding process, so turning processing the surface roughness of the only requirements to Ra0.1? M, turning processing’s main purpose is to get the concave and convex shape accuracy has certain arc surface, the main requirements for tool is the sharpness of the edges. Contact lenses head shape tool as shown in figure 3 below. To meet the need of cutting concave circular arc, the 15 ° after the horn, requirements in 100 times the blade microscope mouth no collapse.

 

3 monocrystalline diamond tool use and maintenance

 

Monocrystalline diamond tool brittleness is big, and very sharp blade, impact blade was easy to produce collapse, so should as far as possible in the stable, no vibration condition use; You should also improve the workpiece and tool as far as possible with rigid and the whole system card rigid, increase its ant-vibration ability. Cutting amount to little more than 0.1 mm is advisable.

 

High cutting speed can reduce the cutting force, and it will increase the low speed cutting cutting force, thus speeding up the blade broke tool failure, so the diamond tool when processing cutting speed shoulds not be too low.

 

Should be avoided in the stationary state makes the diamond tool and workpiece or other good thing contact, to prevent the bruise cutting tools. The operating personnel nails and fingerprints to such as sand entrainment hard thing, with his nails or finger directly scraped may also damage the diamond blade blade. The diamond tool in the detection and blade adjustment by optical instruments should be non-contact measurement method.