Ceramic

Key facts and history

Humans have been making ceramics for at least 26,000 years, subjecting clay and silica to intense heat to fuse them.^[3] The earliest known pottery was made by mixing animal products with clay and firing it at up to 800 °C.^[3] The Mycenaean Greek term ke-ra-me-we, which refers to ceramic workers and appears in Linear B script, provides the earliest recorded instance of the root ceram-.^[4] The oldest ceramic artifacts discovered are sculpted figures originating from south-central Europe, rather than functional vessels.^[3]

Fired clay bricks, employed for constructing house walls, represent the earliest ceramics produced by humans.^[5] Subsequently, ceramics were glazed and then fired to achieve smooth, colored surfaces and to reduce their porosity.^[5] The scope of ceramics today encompasses domestic items, industrial components, building materials, and sophisticated engineering materials such as semiconductors.^[5] Ceramics are generally capable of enduring extremely high temperatures, specifically within a range of 1,000 °C to 1,600 °C.^[2]

What the research sources say

The Materials Science and Engineering Education account states that archeologists have uncovered human-made ceramics dating back to at least 24,000 BC, found in Czechoslovakia as animal and human figurines.^[6] The same source notes these ceramics were made of animal fat and bone mixed with bone ash and a fine claylike material, fired in domed and horseshoe shaped kilns.^[6] The DoITPoMS resource further describes that a volume increase from the high-temperature austenite phase to the martensite phase decreases local tensile stress at the crack tip.^[7] According to the DoITPoMS resource, certain ceramics undergo a stress-induced martensitic transformation; this process absorbs energy, which impedes crack growth and thereby enhances the material's toughness.^[7]