Bending strength
Bending strength describes the mechanical strength of a material under bending stress. The bending strength of ceramic materials is tested primarily on bars with a known cross section made of dried (dry bending strength) or fired or sintered (flame bending strength) material. The cross section of the test specimens is preferably rectangular, trapezoidal or circular. The bars are placed on appropriate bearings and an increasing load is applied in the middle until they break. The breaking force is determined and the bending moment at the point the load is introduced is calculated, taking into account the distance between the supporting bearings. From this, the bending strength of the ceramic rod can be determined, divided by the moment of resistance, which depends on the cross section of the test specimen. For silicate-ceramic materials, the bending strength is determined using a 3-point bending test, while in high-performance ceramics or technical ceramics, use of a 4-point bending test is preferred.