## 7 Conclusions  
In this paper, the preparation process of an ultrasonic-vibration-assisted laser cladding structured CBN grinding wheel was studied. The specific research results are as follows:  
1. The effects of laser power, sweep speed, powder feeding speed, and ultrasonic power on the shape coefficient and dilution rate of the printing layer were analyzed through single-factor experiments. With the gradual increase in laser power, the melt width B and the melt height H increased. As the sweep speed gradually increased, the melt width B and the melt height H decreased. With the increase in the powder feeding speed, the melt width B was reduced and the melt height H increased, while the melt depth h remained basically unchanged. With the increase in ultrasonic power, the width B and height H did not change significantly, and basically maintained stability, while the penetration depth increased slightly.
2. The optimal range of influencing factors such as laser power, sweep speed, powder feeding speed, and ultrasonic power was determined. The level values for laser power were 220 W, 235 W, and 250 W; the level values for sweep speed were 5 mm/s, 6 mm/s, and 7 mm/s; and the level values for powder feeding speed were 1.7 r/min, 1.8 r/min, and 1.9 r/min. The ultrasonic power level values were 5%, 10%, and 15%.
3. Range analysis and variance analysis of the experimental results were carried out through orthogonal experiments. The most significant influence on the shape factor \(\gamma\) was the sweep speed, followed by powder feeding speed and laser power. The most significant influence on the height of the printing layer H was laser power and sweep speed. The corresponding optimal parameters were a laser power of 235 W, a sweep speed of 6 mm/s, a powder feeding speed of 1.8 r/min, and an ultrasonic power percentage of 15%. Thus, process parameter optimization was realized.
4. By comparing the two kinds of grinding wheel printing layers prepared with and without ultrasonic vibration, it was found that the ultrasonic effects can provide the printing layer with better surface morphology constraints. The height of each printing layer was more consistent and the CBN distribution inside the melt pool was uniform. In the case of applying ultrasonic vibration, the difference between the highest point and the lowest point of the exposed height of the CBN particles was small at about 484 um, while the size of the interval without ultrasonic vibration was 1075 um. It is proven that ultrasonic vibration can stabilize the protrusion height of CBN abrasive particles in a range. The sticky powder phenomenon on the surface of the printing layer and the grinding wheel was also improved.  
Figure 14: The prepared grinding wheel.  
**Author Contributions:** Conceptualization, J.L. and M.M.; methodology J.L. and M.L.; software, J.L. and M.M.; formal analysis, J.L. and M.M.; investigation, J.L., M.M. and M.L.; resources, M.M.; writing--original draft preparation, J.L.; writing--review and editing, J.L., T.Y. and J.Z.; visualization, J.L.; supervision, T.Y. and J.Z.; funding acquisition, T.Y. and M.L. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by [the National Natural Science Foundation of China] grant number [52075088, 52305453], [the Fundamental Research Funds for the Central Universities] grant number [N2423023, N2223012], [the Natural Science Foundation of Hebei Province] grant number [E2021501027], and [Science and Technology Project of Hebei Education Department] grant number [QN2022204].  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The original contributions presented in the study are included in the article, further inquiries can be directed to the corresponding authors.  
**Conflicts of Interest:** The authors declare no conflicts of interest.