Tests Offered

Materials testing is a well-established technique used to determine the physical and mechanical properties of raw materials and components from a human hair to metals & alloys, composite materials, ceramics and many more. There are many tests that can be done on materials to determine their properties.

The tests can be either destructive or non-destructive. Destructive tests are often conducted to determine a speciic property of the material/component being tested. They usually require a speciically shaped test piece to be made and this is damaged/destroyed during testing. Examples of destructive tests are tensile, compression, lexural, impact, and fatigue tests. Hardness tests are also done on test pieces (destructive). Additionally, hardness tests are often done on actual components (non-destructive). The ield of testing has a huge vocabulary describing the techniques and processes utilized to obtain test results on materials.

The following glossary of terms and deinitions contains many expressions that are heard and seen often.

Overview of Terminology in Mechanical Testing
Hardness is the resistance of a material to deformation, particularly permanent deformation, indentation or scratching.
Ductilityis the ability of a material to deform to a permanent position before it fractures.
Elastic Limit is maximum stress that a material can sustain without any permanent deformation remaining after complete release of the stress.
Ultimate Tensile Strength is the maximum tensile stress that a material is capable of sustaining and is calculated as the maximum load during a tension test carried to rupture, divided by the original crosssectional area of the sample.
Yield Strength is the engineering stress at which the permanent deformation of the sample has begun.
Young’s Modulus of Elasticity is the ratio of the stress to the corresponding strain below the proportional limit and the greatest stress that the sample can sustain without deviation from a linear relationship of stress to strain.
%Elongation at Break or Total % Elongation is the amount of permanent deformation determined after fracture by realigning and itting together the broken ends of the specimen.
Reduction of Area is measure of the difference of the cross-sectional area of a tensile specimen before and after fracture. Percent reduction of area is a ration that expresses how much the specimen narrowed when compared to its original size.
Crack Growth Rate is the change in length of a crack per number of load cycles. This data enables estimates to be made of the remaining fatigue life of crack exist in the component before a dangerous crack size is reached.
Fatigue – progressive and localized structural damage that occurs when a material is subjected to cyclic loading.
Plastic strain ratio – The ratio of the true strain in the width direction to the true strain in the thickness direction of a sheet material loaded beyond yield.
Strain Hardening Exponent “n” is a measure of the increase in hardness and strength caused by the permanent deformation of a tensile sample. “n” is the calculated exponent of the power curve obtained by mathematically approximating the shape of the stress strain curve between yield and ultimate stress.