Ceramic Tensile Strength

The tensile strength of ceramics and glasses is low because the existing flaws internal or surface cracks act as stress concentrators.

Ceramic tensile strength. Standard test method for tensile strength of monolithic advanced ceramics at ambient temperatures. Standard test method for elevated temperature tensile creep strain creep strain rate and creep time to failure for monolithic advanced ceramics. Alumina for example has a tensile strength of 20 000 psi 1138 mpa while the compressive strength is 350 000 psi 2400 mpa. Ceramics have compressive strengths about ten times higher than their tensile strength.

They provide high wear heat and corrosion resistance as well as high tensile strength volume resistivity dielectric strength and modulus of elasticity. For a metal the compressive strength is near that of the tensile strength while for a ceramic the compressive strength may be 10 times the tensile strength. Ceramics containing a single phase are usually stronger than those with several phases. For a metal the compressive strength is near that of the tensile strength while for a ceramic the compressive strength may be 10 times the tensile strength.

Ceramic materials are usually assumed linear elastic up to failure and the failure criterion is accustomed to be a limit condition related to the tensile strength. Cmc materials with a low fiber content down to zero have a high bending strength close to the strength of the monolithic ceramic but no elongation beyond 0 05 under tensile load. Ceramics tend to be weak in tension but strong in compression. Cmc materials with a low matrix content down to zero have a high tensile strength close to the tensile strength of the fiber but low bending strength.

Tensile strength σ psi compressive strength σ psi flexural strength σ psi modulus of elasticity e 10 6 psi porcelain. Usually ceramic strength is tested using a four point bend test. The properties and the processing of ceramics are largely affected by their grain sizes and shapes and characteristics such as density hardness mechanical strength and optical properties strongly correlate with the microstructure of the sintered piece.