Tool for specialized coating before polishing , thereby significantly improve the quality of the coating.
To improve the quality of the cutting tool and the die , often called the hard coat layer may be coated in the tool and die . This coating process is the use of physical vapor deposition (PVD) or chemical vapor deposition (CVD) process for coating . By means of a hard coating can improve the durability of the tool or the maximum limit of the degree of improved cutting tools . The quality of the coating surface largely depends on the quality of the tool , and a deburring tool sharp status conditions .

Figure 1
Figure 2 is not polished cutter ( left ): Ra = 0.31μm, Rz = 1.0μm;
After milling polished (right ): Ra = 0.03μm, Rz = 0.2μm;
Smooth surface to reduce the impact scars

The tool surface more smooth flow of chips is more smooth, will lower the temperature on the chip . Thus , the tool also can use higher cutting speeds , and significantly improve the durability of the tool . Tool smooth surface also reduces the risk of the material to be machined with welding . Taps for Taps and squeeze it . Required cutting force can significantly be reduced by 40 %.
In general, the need to improve the surface roughness of the coating characteristic values ​​, therefore , the table and before the coating of the surface finish required . If you adopt from Germany施特劳the Hardt - Fairbanks Troon process Eisenach (Straubenhardt-Feldrennach) of奥特克(Otec) Company DF series polishing machine , the tip portion of these irregularities on the surface of the part on the been rounded ( Figure 1 ) , thereby reducing the roughness of the surface of the part , and significantly reduce scar effects.
Otec adoption of a new technology can be as special carbide cutter drill flutes and polished to a mirror . Here the length of the longer milling , the advantages of the flute , the more prominent after polishing .
Residual burrs increased wear

For high-speed steel cutting tools usually appear glitches. If you do not get rid of the glitches before the coating , then the tool during the initial processing glitch is easy to break. This will be a no gloss coating covering a period . In this part of the tool will certainly quickly produce wear. On Otec company DF series polishing machine can effectively remove such burrs , burr they will not have this problem .
Surface defects reduce the stability of the cutting edges

The tool cutting edge position of processing stability , consistency and workpiece surface quality to achieve the most important criteria .

Figure 3 a carbide cutter cutting edges polished before and after the conduct of the company Otec DF series polishing machine . Before polishing, cutting blade surface is very uneven , and there is a small scar .
Figure 3 is a carbide cutter for cutting edges before and after the polishing process in the case of the polishing machine DF Otec company . In the figure we can clearly see the cutting blade of the blade front surface polishing process is very uneven , and there is a small scar . With such a milling cutter would have the following drawbacks when cutting :
Because carbide is relatively brittle , due to the large compressive stress , carbide cutting edges prone to rupture - especially when cutting both hard and tough material, such as cutting quality steel materials. Such a rupture may be very small, but still relatively large . Over time, the wear of the cutting edge itself is gradually rounded . But can not be controlled. Then the stability of cutting tools sharp decline . Because the coating has been destroyed . Similarly, to be achieved on the surface quality was severely damaged .
By using Otec company polishing process so that the cutting edge rounding to obtain a stable and uniform blunt blade . Because of the additional cutting surface to improve the quality of the blade to obtain BU out effect:
Tool life by up to 500%.
Surface quality - the cutting edges have a uniform lower Ra value.
The cutting process can be reliably performed , because the tool to avoid cracking .
Due to the high stability of the cutting edge , it can use higher cutting speed ( cutting speed increased up to 3.5 -fold ) .
Produces less corrugated surface processing ( particularly when cutting aluminum , if the cutting edge is too sharp as it can cause vibration and noise ) .
Blunt cutting edge come the following sizes ( eg carbide cutter ) based on actual production experience :

Figure 4 DF rotary drag -type polishing machine and then processed to remove droplets.
Processing aluminum : 10μm, the DF time of machining polishing ( 1-2 ) minutes.
Processing of steel : (20 ~ 30) μm, the DF time of machining polishing (4-8 ) minutes.
Processing of high-quality steel parts : less than 40μm, the DF polishing machining time up to 12 minutes .
According to the reasons stated above, the use of these tools before coating Otec 's DF polishing machine for polishing is reasonable. After the PVD coating on the surface of the tool is slightly worse than the previous number of gloss (due to the formation of so-called droplets ) . When the rotary drag DF Otec 's polishing machine further processing, the droplets can be effectively removed ( Figure 4 ) .