Diamond Grinding

[Met.Eng.]

Hi Gordon,

We decided to buy Diamond for grinding. ( for WC Co, CrC NiCr , Al2O3 TiO2 and Cr2O3..ect)

Can you help us to choice the type of diamond? There are many types on the market. What we should note that the selection of diamond grinding? We can do superfinish with diamond abrasive strip. But we must give to rough "non-sensitive" sawdust.

[LEN WOOD]

What surface finishes and work environments are you looking for with your different applications?

[Stephen Booth]

Hi Metal Eng,

I have been very successful using Flexible Diamond Belts in a belt grinding attachment or retrofit equipment (adapting the belt to work in existing grinder). Many of the belts are graded in microns, typically on an as sprayed HVOF coating of WC the starting Ra value is about Ra 5, we start with a 125 micron belt, then move to a 74 micron, 40 micron, 20 micron, and in many cases stop with the 10 micron belts.

Superfinishing or microfinishing can reduce the Ra, Rz, etc even lower, and like Len says, all depends on the application.

Maybe you are looking for a rough finish? That can be done with slack belt grinding, and jumping a few steps on the diamond grades mentioned above.

Belts are avaiable from KGS and 3M

[Met.Eng.]

Hi Stephen Booth

I have KGS's belds too.400 800,1500,3000 ect,Grit. But some times we grind 500 micron WC surface (out of the overflowing, the excess coated part). its too difficult to scratch 100 micron or higher coated surface.

[Stephen Booth]

I spoke with the KGS people and they recommended 120 mesh for grinding on overspray other wise damages the belts

[Stephen Booth]

More information from KGS

In answer to overspray you can use 4” discs on a hand grinder.

Use KGS Telum. I have a number of customers that use them. Also you can use belts 915 x25 in KGS Switlex TCH on a Dynabrade Dynafile type machine.

This is preferred because it is a quick touch up job when the piece is still turning on the lathe.

You can also buy belts in the same grits as the large belts so blending is very good.

[Stephen Booth]

http://www.bexxonglobal.com/diamond-belt-grinding2.html

check out KGS Swiss Diamond

[Stephen Booth]

http://www.bexxonglobal.com/kgs-microfin...shers.html

We now have superfinishers and polishers as well as belt grinders...

[Artyom]

Hello Met.Eng.

For ceramic and cermet coatings you can try a diamond wheel with the following parameters:
1) Synthetic single-crystal diamond powder AC4
2) Grain size 160/125micron
3) Bakelite binder

Recommended grinding parameters
1) Depth of cut 0.01-0.02 mm
2) Part's peripheral speed 5 m/min
3) Axial feed - wheel width*0.1 for one rotation of a part
4) Coolant usage is required

For fine polishing we have used diamond strips, but unfortunately I can't recall their parameters.