Machine Grade Fused Silica Lubrication

[Metalhead97]

I'm designing a direct chill tilt-pour casting mold. Fused silica will be used for part of the mold. I have found a supplier of machine grade fused silica. I personally have never machined a ceramic and our machine shop also has close to nil experience. What is the extent of the lubrication that is required. Is spraying a continuous stream okay or should flooding be used? The manufacture says use 'lots' of lubrication or risk chipping the part. Thanks for any input. The raw material isn't cheap and I would hate to ruin a part for lack of proper lubrication. Thanks.

Metalhead

 

[Compositepro]

Yes, use flood coolant. Selection of abrasives and tool feed rate (slow) is also important.

 

[Metalhead97]

Thanks for the response. Just to clarify a continuous stream hitting the machined spot isn't enough?

Interestingly enough, the data sheet says the ceramic can be machined with carbide tip tools as long as there is plenty of lubrication. I'm assuming this goes for both cutting and drilling operations.

Thanks

Metalhead

 

[Compositepro]

Continuous stream will work. Carbide will work as long as the edges stay sharp. You will know it gets dull when the quartz breaks. I would suggest that diamond abrasive is better.