Influence of PCD cutting parameters on cutting performance

(1) cutting speed

PCD tools can be machined at extremely high spindle speeds, but at low cutting speeds

The effect of the change on the processing quality can not be ignored.Although high speed cutting can improve machining efficiency, in high speed cutting state, the increase of cutting temperature and cutting force can damage the tool tip and make the machine vibrate.When machining different workpiece materials, the reasonable cutting speed of PCD cutter is also different. For example, the reasonable cutting speed of milling Al2O3 laminate floor is 110-120m /min.The reasonable cutting speed of SiC particle reinforced aluminum matrix composites and sio2 based engineering ceramics is 30 ~ 40m/min.

(2) feed quantity

If the feed of PCD cutter is too large, the residual geometric area of the workpiece will increase, resulting in the increase of surface roughness;If the feed is too small, it will make the cutting temperature rise, cutting life reduced.

(3) cutting depth

Increasing the cutting depth of PCD tool will increase the cutting force and cutting heat, thus aggravating tool wear and affecting tool life.In addition, the increase of cutting depth can easily cause PCD tool edge breakage.

PCD tools with different particle sizes have different cutting properties when machining different workpiece materials under different processing conditions. Therefore, the actual cutting parameters of PCD tools should be determined according to specific processing conditions.

4.2 failure mechanism of PCD tools

The tool wear mainly includes abrasive wear, bonding wear (cold welding wear), diffusion wear, oxidation wear, thermoelectric wear and so on.The failure mode of PCD tools is different from that of traditional tools, which is mainly manifested as polycrystalline layer damage, adhesive wear and diffusion wear.The results show that when PCD tool is used to process metal matrix composites, the failure forms are mainly bond wear and intergranular crack caused by diamond grain defect.When machining high hardness and high brittleness materials, the adhesive wear of PCD tool is not obvious.On the contrary, when machining low brittle materials (such as carbon fiber reinforced materials), tool wear increases, and adhesive wear plays a leading role.