## 4 Abrasive Belt Wear Measurement Test
### Test Data Analysis  
This group of experiments uses a single factor independent variable to study the relationship between the abrasive belt wear rate and the grinding parameters (grinding speed and contact pressure) and the workpiece material. The characteristic parameter is the abrasive belt height wear rate. Due to the high randomness of sanding belt's abrasive height, in order to reduce the error as much as possible, 15 min is used as the unit time, and the wear amount is counted every 15 min.  
(1) The influence of grinding speed on wear rate  
Figure 12 is a graph showing the change in the wear rate of different materials with the grinding speed under a contact pressure of 5 N. It can be seen from the figure that the abrasive belt wear rate gradually increases as the grinding speed \(v\) of the abrasive belt changes from 2 m/s to 8 m/s. The reason is that increasing the grinding speed of the abrasive belt within the same time will increase the number of abrasive particles  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multicolumn{6}{c}{\#45 under 5 N contact load} & \multicolumn{3}{c}{\#45 under 5 N contact load after grinding} \\ \hline
191.1 & 198.3 & 182.1 & 183.9 & 175.8 & 181.2 \\ \hline \multicolumn{6}{c}{\#45 under 10 N contact load} & \multicolumn{3}{c}{\#45 under 10 N contact load after grinding} \\ \hline
154.1 & 164.9 & 162.2 & 135.2 & 146.0 & 151.4 \\ \hline \multicolumn{6}{c}{\#45 under 15 N contact load} & \multicolumn{3}{c}{\#45 under 15 N contact load after grinding} \\ \hline
94.6 & 81.1 & 97.3 & 78.4 & 67.6 & 70.3 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Measured data of abrasive heights for #45 steels (\(\upmu\)m).  
\begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline Number & 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 \\ \hline \(\Delta h\) & 10.0 & 5.7 & 4.2 & 7.6 & 10.2 & 14.1 & 24.7 & 17.1 & 8.9 \\ \hline Number & 10 & 11 & 12 & 13 & 14 & 15 & 16 & 17 & 18 \\ \hline \(\Delta h\) & 10.2 & 5.7 & 4.  
contacting the workpiece. As the speed continues to increase, the increase in the wear rate increases accordingly. Meanwhile, different materials also have a certain impact on the wear rate. With the increase of steel grade, the hardness of the steel structure increases, which intensifies the abrasive belt wear. With the increase of grinding speed, the increase of the wear rate of hard materials is relatively stable. Therefore, the difference in materials has less superimposed effect on the change of grinding speed.  
(2) Influence of contact pressure on wear rate  
Figure 13 shows the change curve of wear rate with contact pressure for different materials at a grinding speed of 8 m/s. According to the figure, it can be seen that when the contact pressure of the abrasive belt is 5-15 N, the high wear rate of the abrasive belt has a huge increase with the increase of the pressure. The contact pressure increases by 10 N, and the wear amount increases by nearly 70%. As the contact pressure increases, the pressure on a single abrasive particle increases, the cutting depth also increases, and the temperature in the contact area increases faster, which ultimately leads to increased wear. At the same time, it can be seen that with the increase of contact pressure, the increase of the wear rate of materials with higher hardness is greater, so the difference of materials has a greater superimposition effect on the change of contact pressure.