Mechanical testing is one of the most common and important forms of quality assurance and failure analysis procedures conducted today. Contemporary mechanical testing is a highly technical and professional occupation that is standardized, scientific, and highly reliable.

This is what you should know about the state of modern professional mechanical testing, including how it works and why you may need it.  

What is mechanical testing?

Mechanical testing is a broad category of tests that measure the properties of a material (such as a metal) under applied dynamic or static force. Mechanical testing is conducted either to determine a material’s mechanical properties – such as its tensile strength or impact resistance – or to determine the response of a material to a given action.

Why is mechanical testing important? 

Mechanical testing is an essential safety and quality assurance step in the design and manufacturing product development processes. The primary purpose of most mechanical testing is to ensure that product developers can safely use the materials tested. 

To determine the safety of these materials, professionals must rigorously test them under all the conditions of their regular use and in all the environments in which they may be used. 

What are the different types of mechanical testing? 

There are seven very broad categories of mechanical testing.

Hardness testing

Hardness testing refers to any test that measures a material’s hardness as a function of its resistance to physical deformation by applied force.

The two main types of hardness testing are indentation testing and scratch testing. 

Indentation testing is performed on materials that undergo plastic (permanent) deformation when penetrated by another, harder material. Indentation testing measures hardness by indenting a sample of the material being tested and measuring the force applied by the indenting instrument against geometrical aspects of the indentation produced, such as its surface area or depth. 

Scratch testing is used to test the hardness of brittle materials such as ceramics. These tests measure a material’s hardness as a function of its resistance to scratches and abrasion. The material will be scratched with another, harder instrument, and testers will measure the force required to produce the scratch against its size and depth. 

Tensile testing

Tensile testing, also known as tension testing, refers to any test in which a material is subjected to controlled tension until it breaks. Tensile tests are conducted to measure how much tension a material can be placed under until it breaks, and how it will react to being placed under dynamic amounts of tension over time. 

During tensile testing, the material being investigated is gripped by an apparatus at both ends. The apparatus then pulls the material in opposite directions with variable force. The material’s reactions to different quantities of force are intermittently measured by testers.

Tensile testing has many applications, but it’s most commonly used to ensure that a material can resist the amount of tension it will be placed under when used for different applications. For example, tensile testing is commonly performed on fasteners and adhesives to ensure they can properly hold together.

Impact testing

Impact testing refers to any test in which a material is subjected to a sudden load of force, usually a blow from a fast-moving, heavy object. This is done to test the material’s toughness as a factor of its ability to absorb force without deforming and can determine whether a material is ductile or brittle.

Impact testing is conducted on materials that will need to withstand such blows during their product applications. It is commonly used to test metal, plastic, resin, and composite materials.

There are four common types of impact testing: Charpy, Izod, drop-weight, and dynamic tear testing. The major difference between each of these types of tests is how the sudden load of force is applied to the material. 

In Charpy and Izod impact testing, a weighted hammer on a pendulum is released from a pre-specified height and collides with the material at the apex of its downward swing. In Drop-weight impact testing and dynamic tear testing, testers fix weight over the material being tested and then drop it from a predetermined height. 

Fracture toughness testing 

Fracture toughness tests apply an ever-increasing load of force to a material over time until that material cracks. After the material cracks, the force is continuously applied to study the material’s resistance to crack propagation, or how quickly and completely the crack spreads across the material and how the crack affects material performance.

Fracture toughness is a very important material property for any product that will be subjected to strain over periods because it will help testers understand exactly how long the material can last under different conditions and amounts of strain, and what will happen when the material starts to fail. 

Creep testing

Creep testing subjects the material being investigated to a continuous tensile or compressive load of force at a constant elevated temperature. This is used to determine how the material will perform under strain over time in environments with elevated temperatures, such as furnaces. It is commonly performed on soldered joints.

Fatigue testing

Fatigue testing subjects the material being investigated to cyclic loading, which is a form of sustained, progressive, and fluctuating force, like what might be caused by vibrations, that strains the material over time. 

Fatigue testing is used to understand how a material will react to the stress of fluctuating, sustained loads of energy over time. It is a very important test for materials that will be relied upon for long periods of time, such as support beams or other building materials.

Non-destructive testing

Non-destructive mechanical testing is a very broad category of testing that measures the mechanical properties of materials without destroying or significantly compromising the structural integrity of the sample.

All forms of non-destructive testing involve using a probing medium of some kind to scan a material for variations in its properties and record these variations. The six most commonly used non-destructive mechanical testing probes are visual, eddy-currents, magnetic particles, liquid penetrants, radiographic, ultrasonic, and visual.

Non-destructive testing requires special certification and training to handle specialized equipment and interpret results with a high degree of accuracy.

How can I get mechanical testing?

If you need mechanical testing, Secat’s experts are ready to help. 

We have state-of-the-art mechanical testing equipment capable of carrying out all forms of testing covered above, and extensive experience conducting mechanical testing for PPAP/First Article inspection, customer part specification, ASTM specification, field failure, manufacturing defect analysis, and more. 

Whatever your mechanical testing needs, Secat’s experts can help you understand the process, interpret the results, and inform your next steps. Get in touch and we can get started right now.