Hardness & Impact Testers

About Hardness & Impact Testers

Hardness tests determine the hardness of any material, and impact testing determines toughness. Hardness testing assesses the impact of the metal or alloy on permanent indentation, and the depth or size of the indent is measured to determine a hardness value.

Hardness testing enables you to evaluate the strength, ductility, and wear resistance, which can determine whether a material is suitable. An impact testing machine determines the resistance of a material or component to a rapid load under varying temperature conditions.

Impact testing involves striking a standard specimen with a controlled weight pendulum travelling at a set speed. The amount of energy absorbed in fracturing the test piece is measured indicating the notch toughness of the test material.

Popular Products

Sauter Leeb HN-D Hardness Tester: The Sauter HN-D contains a built-in Type-D impact sensor and an accuracy of ±4 HLD. It has Rockwell (B & C), Vickers (HV), Brinell (HB), Shore (HSD), and Leeb (HL) measurement units.
Mitutoyo Series 810, HM Micro-Vickers Hardness Testing Machine: Test force between 0.05gf to 2kg with the latest electromagnetic force motor technology. 10X, 20X, 50X, and 100X for measuring indentation images and 2X and 5X for wide-range measurement around indentations. Available with a choice of four systems.
Sauter HMM Mobile Leeb Hardness Tester: The tester has an external type-D impact sensor supported by a spring placed against the tested item. Automatically converts the measured value into a user-specified unit and includes a selection of statistical functions.
Mitutoyo 3 Piece Reference Material Shore A or D: Select your test block set from the Shore D calibration set with 00-DURO-Blue, 40-DURO-Gray, and 80-DURO-Black blocks and the Shore A collection with 30-DURO-Blue, 60-DURO-Yellow, and 90-DURO-Gray blocks, all housed in a mahogany case.
Sauter TVO LD Test Stand Set: Practical solutions for force-displacement measurements. These versatile systems include a motorized test stand, length measuring system LD, interface cable, data transfer software AFH LD, interface converter AFH 12, and mounting equipment. Can accommodate SAUTER force measuring devices up to 500 N, 1 kN, or 2 kN.

FAQs

What materials can hardness testers measure?
They can measure various materials, including metals (including steel, aluminium, copper, and titanium), plastics (thermoplastics, thermosetting plastics, and elastomers), ceramics (like porcelain and silicon carbide), composites (fibre-reinforced polymers and concrete), wood, soft materials (gels and foams), and thin films or coatings. Each material type may require specific testing methods.
How do I perform a Charpy impact test?
Prepare a standard specimen with a V-shaped notch. Place the specimen horizontally in the testing machine with the notch facing the impact direction, and set the pendulum to the desired height. Release the pendulum to strike the specimen at the notch. Record the energy absorbed during the impact and measure the difference in the pendulum height before and after the strike. Refer to standards like ASTM E23 for detailed specifications.
What is the difference between Rockwell, Brinell, and Vickers hardness tests?
The Rockwell test measures hardness by assessing the depth of penetration of a ball or diamond cone indenter under a large load following the application of an initial minor load. The Brinell test involves pressing a steel or carbide ball into the material under a specific load and measuring the diameter of the resulting indentation. The Vickers test employs a diamond pyramid indenter to create an indentation, with hardness calculated from the indentation's size.
What are some common misconceptions about hardness testing?
1. Hardness directly correlates with the overall strength of a material.
  While hardness indicates resistance to deformation of the material, it does not necessarily mean the material is strong in other ways, such as tensile or impact strength.
2. Different hardness scales (e.g., Rockwell, Brinell, and Vickers) are interchangeable.
  These scales measure hardness using various methods and units, so direct comparisons can be inaccurate unless correctly converted.
3. One test in one location of the material provides a complete picture.
  Materials can have varying hardness across their surface or depth, and multiple tests are often necessary for a reliable assessment.
4. All hardness testers evaluate the identical characteristics of the material.
  Different tests (like Vickers, Brinell, and Rockwell) may focus on resistance to penetration, scratch resistance, or other specific properties.
5. Hardness only relates to wear resistance and doesn't impact other properties.
  Hardness can influence factors like brittleness, fatigue resistance, and machinability.
6. Any hardness test will yield the same result regardless of the method used.
  Different tests are suited for various materials and applications, and selecting the wrong method can lead to inaccurate results.
What are the challenges of testing materials with extreme hardness levels?
Challenges include difficulty creating measurable indentations, rapid equipment wear, and the necessity for specialised indenters. Surface preparation becomes critical, as poor finishes may affect accuracy, and brittle materials risk cracking during tests. Specialised testing methods like Vickers or Knoop may be required.
What role does operator skill play in the reliability of hardness and impact test results?
Skilled operators prepare specimens correctly, set up and calibrate equipment, and apply the appropriate force consistently. They accurately interpret results and identify potential sources of error.
How do I adapt hardness testing methods for unconventional materials?
It requires appropriate test techniques based on the material's properties. Modify testing conditions, like load and dwell time, to prevent excessive deformation. Correctly prepare the sample, including polishing, and conduct tests in controlled environmental conditions.