What is a key cause of rough surface or porosity in porcelain?

The key cause of rough surface or porosity in porcelain can often be attributed to lack of compression. During the fabrication process, porcelain must be properly compressed to eliminate air bubbles and ensure a dense, uniform structure. If the material is not adequately compressed, it can lead to inconsistencies in the porcelain, manifesting as rough surfaces or porosity. This lack of density can compromise the final product's aesthetic quality and mechanical strength.

While aspects such as temperature fluctuations or heating times can affect the results of porcelain firing, they primarily influence other properties rather than directly causing rough surfaces or porosity. Similarly, improper mixing might lead to issues with color uniformity or strength but is not the primary factor leading to surface texture problems. Therefore, the emphasis on compression highlights the importance of properly preparing and handling the porcelain to achieve the desired smoothness and integrity in the final product.