# Research on Grinding Force of Ultrasonic Vibration-Assisted Grinding of C/SiC Composite Materials
## 3 Result and Discussion
### Influence of Main Processing Parameters  
When using common grinding and UVAG to process the side of C/SiC composite material, the influence of the process parameters on the grinding force in the two states is shown in Figures 6-8, respectively. Under all test conditions, UVAG can significantly reduce the grinding force. The maximum reduction range of normal grinding force and tangential grinding force is about 25%.  
Figure 6 shows the influence of grinding speed changes on the grinding force. With the increase in grinding speed, the grinding force of common grinding and UVAG has a downward trend. In addition, the amplitude of reducing cutting force by UVAG is lower than that of common grinding. This indicates that with the increase in the grinding speed, the ultrasonic assisting effect on the machining process tends to weaken. Figure 7 shows the influence law of grinding depth changes on the grinding force. With the increase in the grinding depth, the cutting force of common grinding and UVAG shows a significant increasing trend. Unlike the characteristics of the grinding speed, the increase in the grinding depth has a relatively small effect on the reduction in the grinding force. Figure 8 shows the law of the influence of the grinding feed speed on the grinding force. With the increase in the grinding feed speed, the grinding force of common grinding and UVAG has an increasing trend. Similarly, the feed speed changes within the range of the parameters have less influence on the ultrasonic assisting effect than the grinding speed.  
Figure 5: **(a)** Typical grinding force signal for side grinding. The process parameters used in image collection are \(v_{\mathrm{s}}=1.26\leavevmode\
obreak\ \mathrm{m}/\mathrm{s},a_{\mathrm{p}}=30 \leavevmode\
obreak\ \mathrm{\SIUnitSymbolMicro m},v_{\mathrm{w}}=100 \leavevmode\
obreak\ \mathrm{mm}/\mathrm{min}\). **(b)** Typical grinding force signal for end grinding. The process parameters used in image collection are \(v_{\mathrm{s}}=1.26\leavevmode\
obreak\ \mathrm{m}/\mathrm{s},a_{\mathrm{p}}=10 \leavevmode\
obreak\ \mathrm{\SIUnitSymbolMicro m}\), \(v_{\mathrm{w}}=100\leavevmode\
obreak\ \mathrm{mm}/\mathrm{min}\).  
Figure 8: Side grinding: the influence of feed speed changes on the grinding force.  
Figure 6: Side grinding: the influence of grinding speed changes on the grinding force.  
Figure 7: Side grinding: the influence of grinding depth changes on the grinding force.  
Figures 9-11, respectively, show the influence of grinding speed, grinding depth, and feed speed on the grinding force during end grinding. Compared with common grinding, UVAG can significantly reduce the grinding force during end grinding of C/SiC composites. The maximum reduction in normal grinding force is about 53%, and the maximum reduction in tangential grinding force is about 40%. As with side grinding, the increase in grinding speed can significantly reduce the amplitude of the grinding force. In addition, changes in feed speed and grinding depth also have a certain influence on grinding force, but the degree of influence is relatively small.  
Figure 10: End grinding: the influence of grinding depth changes on the grinding force.  
Figure 9: End grinding: the influence of grinding speed changes on the grinding force.