# Feasibility Study of Integrated Precision Abrasive Machining of Shaped Surfaces
## 4 Conclusions  
As a result of the design and verification work carried out, the following specific conclusions were formulated.  
* The conducted tests of the grinding process showed a reduction in the values of the roughness parameters _Sa_ (5.30, 1.12, 0.63 \(\upmu\)m), _St_ (31.8, 14.4, 6.72 \(\upmu\)m), _Sq_ (6.39, 1.46, 0.81 \(\upmu\)m) and _Spk_ (6.16, 0.77, 0. 33 \(\upmu\)m), and an increase in the value of the parameter _Sds_ (393, 563, 1203 pks/mm\({}^{2}\)) on the surface after machining in two stages, first for rough grinding and then for finishing; this was relative to the surface after the shaped milling process.
* The value of the _Str_ parameter changed unevenly during the tests. It first decreased during coarse grinding (from a value of 0.03 to 0.0187), and then increased during finishing (from a value of 0.0187 to 0.0367). This is due to the fact that first, a grinding wheel was used that made linear contact with the workpiece during grinding, and then a wheel was used that ground the workpiece with its entire circumference.
* Microscopic analysis showed that the ceramic grinding wheel exhibited numerous inclusions and seizures with the workpiece material. Most likely, this is due to the insufficient openness of the grinding wheel structure and the adhesion of grinding products (mainly chips of workpiece material) to its active surface.
* Microscopic analysis of the active surface of the prone grinding wheel shows that the grains are only moderately worn. The magnifications show some chipped grains, but they are so few that the wheel is suitable for grinding subsequent samples while ensuring the full repeatability of the geometric structure of the machined surface.  
The study confirmed that the use of a dual-tool grinding head is an innovative way to carry out the roughing and finishing grinding process in a single fixture. The conducted tests made it possible to determine both the strengths of the dual-tool grinding head, such as the possibility of complete machining in one clamping, and the weaknesses, such as the speed of rotation that the head can reach, the limitations of the tool geometry and the formation of deposits on the ceramic grinding wheel. This will allow for the elimination of detected imperfections and a further analysis of the strategies that could be used for integrating machining operations. In further research, it should be verified whether the problem of seizing the ceramic grinding wheel is reduced by increasing the porosity (openness of the structure) of the wheel and intensifying the cooling, in order to more precisely reach the anti-adhesive agents that are contained in the coolant for the grinding zone.  
Conceptualization, P.J. and K.N.; methodology, P.J. and K.N.; software, P.J., T.C. and W.Z.; validation, K.N.; formal analysis, P.J. and K.N.; investigation, P.J. and W.Z.; resources, K.N.; data curation, P.J., T.C. and W.Z.; writing--original draft preparation, P.J.; writing--review and editing, K.N.; visualization, P.J., T.C. and W.Z.; supervision, K.N.; project administration, K.N.; funding acquisition, K.N. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
The authors sincerely thank two companies for their cooperation. First, they thank ANDRE ABRASIVE ARTICLES limited liability company, limited partnership, including [PERSON], the customer service specialist, for her assistance in selecting and designing suitable ceramic grinding wheels. In addition, the authors would like to thank KEYENCE INTERNATIONAL (BELGIUM) NV/SA, including [PERSON], for his assistance in recording images using a digital microscope.  
The authors declare no conflict of interest.