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Impact Testers and Charpy Impact Testers

Testing machines for determination of the impact strength of plastics and metals

...the right impact test equipment for standard-compliant testing!

An impact testing machine helps determine the resistance of a material or component to a rapid load under varying environmental conditions. Because many materials used for a number of different applications on a daily basis are subjected to fluctuating temperatures, and since the fracture or failure behavior also depends on temperature, these materials must often be tested in their entire operating temperature range. These tests are used to indicate at what temperature and to what extent the material becomes brittle.

Pendulum impact tester Drop weight tester Videos FAQ Customer cases

ZwickRoell impact strength testing machines: the right pendulum impact testers and drop weight testers for your applications

Impact testing has become firmly established in materials and components testing. The properties determined are part of basic material characterization. ZwickRoell has been delivering quality impact test equipment for years. Our product line includes pendulum impact testers for metals and pendulum impact testers for plastics, drop weight testers with an energy range of only a few joules to 100,000 joules, as well as hydraulic high-speed testing machines.

  • The energy range of our machines spans from 5.5 joules (pendulum impact testers) to 100,000 joules (drop weight testers).
  • Our impact testing machines are available in conventional (non-instrumented) and instrumented versions.
  • Our specimen temperature conditioning box and magazine ensure precise specimen preparation and standard-compliant testing.
  • The use of automated solutions with our impact testers further increases reliability and cost-effective test processes.

With just one click you, can learn more about our different options for impact testing:

Pendulum impact testers up to 750 joules

Drop weight testers up to 20,000 joules

Rebound resilience testers

Impact tests on plastics

Impact tests on plastics

Impact tests on plastics – non-instrumented
Impact tests on plastics – instrumented
Impact tests on elastomers and foam

Impact tests on plastics – non-instrumented

There are ISO product, method, and instrument standards for impact tests with pendulum impact testers.

Product and method standards describe how specimens are taken from a variety of materials and tested. Or they describe a test method for a product or material group.

Instrument standards describe how test instruments are designed. They specify the technical data and their tolerances and define how testing instruments should be verified.

While our customers rely on product standards, as a manufacturer of instruments, both product standards (for the test sequence) and instrument standards (for the technical design of the test instrument) are binding. Therefore both groups of standards are listed below.

As a rule, ASTM standards do not differentiate between product, method, or instrument standards.

Impact tests on plastics – instrumented

The following characteristics are determined in instrumented Charpy tests to ISO 179-2:

  • Maximum force
  • Deflection at maximum force
  • Energy up to maximum force
  • Deflection at break
  • Energy at break

Impact tests on elastomers and foam

The objective of tests on elastomers and foams is the straightforward and fast measurement of material elasticity.

One material that is up to 100% elastic stores supplied energy and releases it at the moment the force is no longer applied. In contrast, material that is up to 100% plastic absorbs supplied energy completely.

These characteristics are used to measure rebound resilience:

A disk-shaped specimen is clamped to a massive block. A pendulum hits the specimen and supplies energy through the hit. The elastic part of the specimen saves the energy (the pendulum rests for a moment) and then returns the energy to the pendulum. The pendulum is accelerated in the opposite direction and swings back.

Once it reaches its resting position after returning, the backward swing angle is measured. Using the angle, the elastic energy that the specimen returned to the pendulum is calculated.

Impact tests on metals

Frequently asked questions about impact testers

Frequently asked questions about impact testers

What is an impact testing machine?
How to use a Charpy impact tester
What is the difference between a non-instrumented and instrumented impact testing machine?

What is an impact testing machine?

An impact testing machine is used to determine the resistance of a material or component to a rapid load under varying temperature conditions. Depending on the material to be tested, end-use application requirements, and the preferred type of test data, a choice is made between pendulum impact testers and drop weight impact testers. As their respective names suggest, specimens are either struck by a swinging pendulum or hit by a falling weight. In each case, the weight, the release height or drop height, and the type of striking hammer or tool that impacts the specimen are pre-defined, and the machine is set up accordingly.

How to use a Charpy impact tester

One of the most common tests performed with pendulum impact testers is the Charpy test, which has also earned these machines the designation of Charpy impact testers or Charpy impact testing machines.

The base components of a Charpy tester are the machine frame, a weighted pendulum rod with hammer, a dial gauge, specimen supports, and a safety shield/device. Complete pendulum impact systems can also include PC equipment and temperature conditioning devices.

For a Charpy test, a notched specimen is centered on the supports horizontally with the notch facing away from the pendulum. The pendulum is released to strike and fracture the specimen. Depending on the objective, application and material of the test being performed, pendulum impact tests can be carried out with either conventional or instrumented equipment.

What is the difference between a non-instrumented and instrumented impact testing machine?

  • In a conventional impact test (not instrumented), the amount of energy absorbed by the specimen during fracture is calculated by comparing the difference of the height of the pendulum before and after the fracture. The energy absorbed is directly related to the brittleness of the material, where brittle materials normally have lower absorption rates than ductile materials.
  • An instrumented impact test measures the force during impact, provides high-speed stress/strain data that differentiates between ductile and brittle failure and provides information on fracture mechanical characteristics. Instrumentation, therefore, allows us to determine the failure mode not just the failure energy.
  • Other frequently used impact tests include the Izod test and impact tensile test. Izod tests, developed by ASTM, are widely used in the North American region, while Charpy tests are more typically utilized in other parts of the world. Tensile impact tests determine a material’s impact energy under tensile loading.

Interesting customer projects with impact testing machines—learn more about how our customers are using our impact test equipment!

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