#### Compression Testing Universal Testing Systems

ADMET material testing systems are ideal for performing compression tests on a variety of products and materials including concrete, metal, cardboard and plastic packaging, ceramics, and composites. The most common measurement obtained from a compression test is the compressive strength which is the maximum stress a material can withstand before it yields or breaks. It is also possible to measure modulus of elasticity, yield stress, and deformation when performing compression tests. Examples of common tests include measuring the point at which a concrete cylinder breaks under a compressive load, or determining the load at various displacements when compressing a block of polyurethane foam.

Common compression testing definitions and keywords include:

• Compressive strength: The maximum compressive stress a material can withstand before it yields or breaks after gradual compression. Compressive strength measurements are expressed in force per unit area.
• Compressive stress: The compressive load per unit area of minimum original cross section. Compressive strength and compressive stress may or may not be the same values. Compressive stress measurements are expressed in force per unit area.
• Compressive deformation: The decrease in the gauge length area of a test specimen resulting from the applied compressive force. Deformation measurements are expressed in units of length.
• Compressive strain: The ratio of compressive deformation to the gauge length of the test specimen, or the change in length per unit of original length along the y-axis. Strain is a ratio, thus is unit-less.
• Compressive yield point: The first point on a material’s compressive stress-strain curve where an increase in the strain value occurs without an increase in the stress value. Compressive yield strength is the stress at the yield point, expressed as force per unit area.
• Modulus of Elasticity: The ratio of the nominal stress to the corresponding strain below the proportional limit of a material. Modulus measurements are expressed in force per unit area.
• Poisson’s ratio: The ratio of the transverse strain to the axial strain. Poisson’s ratio is a dimensionless ratio.

Common compression testing standards include:

## eXpert 2600 Dual Column Testing Machine

The eXpert 2600 series universal testing machines are available in table top or floor standing configurations from 2kN to 600kN.

## eXpert 5000 Modular Testing Machine

The eXpert 5000 series testing machines feature configurable frame components and a detachable actuator, giving you the ability to configure your system in a variety of vertical or horizontal orientations.

## eXpert 7600 Single Column Testing Machine

The eXpert 7600 series single column testing machines are capable of performing tension, compression, flexure and peel/adhesion tests in an affordable and compact package.