Ceramic raw materials for porcelain: For preparing porcelain bodies (e.g., electrical porcelain, tableware), the selected clay should meet which key requirements of quality and workability?

Introduction / Context:

Porcelain is a vitrified, high-strength ceramic made from a carefully proportioned mixture of kaolin (china clay), feldspar, and quartz. The quality of the clay component strongly influences plastic forming behavior, defect rates, and final appearance (whiteness/translucency).

Given Data / Assumptions:

• Clay refers to kaolin and plastic clays used in porcelain formulations.
• Manufacturing steps include plastic shaping (throwing, pressing) or slip casting, followed by drying and high-temperature firing.
• Impurity control is crucial for electrical and sanitary porcelains.

Concept / Approach:

Porcelain clays must be pure (low iron/titanium to avoid discoloration), have good plasticity for forming without cracking, and possess sufficient tenacity/green strength to survive handling and drying prior to firing. These requirements are complementary; compromising any one increases defects (warping, laminations, discoloration).

Step-by-Step Solution:

Verification / Alternative check:

Porcelain body recipes and standards emphasize low Fe/Ti content, controlled particle size for plasticity, and adequate green strength—supporting the combined requirement.

Why Other Options Are Wrong:

• Choosing a single property neglects the interdependence among purity, plasticity, and green strength.
• High refractoriness only without purity or plasticity is insufficient for porcelain quality.

Common Pitfalls:

• Overlooking deflocculation and water content control, which also affect plasticity and green strength.

Final Answer:

All the above