What is portable hardness tester?

22nd February 2021

What’s the portable hardness tester?

In order to reduce raw material costs and increase the quality and reliability of what is produced, several industrial sectors have adopted the practice of using portable hardness measurement. It is a tool made up of several very precise hardness measurement techniques that generate reliable results during inspection. The portable hardness tester is applied both to large pieces of great thickness, as well as small pieces of very thin thickness and also to components with restricted access.

The hardness meter basically operates in two ways. One is the so-called static method, which results from the ratio between the applied load and the formation of permanent indentation. The other mode, known as dynamic, presents results derived from the loss of energy from the tip of the hardness meter.

The applications of portable hardness tester?

  1. Rebound hardness tester: also called in other ways such as Leeb hardness test (name from which the operating principle comes from), impact instrument or impact hardness tester. This particular instrument is definitely the most widespread for 2 particular reasons, the first dictated by the simplicity of use and the second for the price, these types of testers are found at very low costs. Suitable for measuring the hardness of steel and cast steel, alloy tool steel, stainless steel, gray cast iron, ductile iron, cast aluminum alloy, copper-zinc alloy (brass), copper-tin (bronze), pure copper, forged steel, etc.
  2. “UCI” (Ultrasonic Contact Impedance) ultrasound testers: an innovative and fairly recent article. It is an instrument that uses the ultrasound principle for the detection of hardness, Ma! some important considerations must be taken into account: This type of Testers is not very suitable for measuring hardness on soft materials, light alloys such as aluminum, iron and more. It finds particular application on the measurement of hard materials or materials subjected to surface hardening, in this case it is the most effective and reliable.
  3. Penetration testers: the last of the three versions and certainly the most complete and versatile. It works on the same principle as the bench testers but using much lower loads, generally from 1 to 5 kg.

How does the portable hardness tester work?

In the industrial segment, many procedures are carried out to check and ensure the quality of finished parts and equipment. Some of these procedures are performed through non-destructive tests, which measure the characteristic property of the material.  For the procedure to be carried out properly, the use of the portable hardness tester is essential especially for metals.

The measurement process, despite demanding a professional, is done in a simple way. The professional positions the portable hardness tester by placing the part between the base and the hydraulic unit until the hydraulic unit touches the part. The pressure release valve is closed, and the hydraulic lever is moved until the desired load is reached. The hardness test applies a load of up to 3000 kg in a 10 mm sphere. In order that the measured part is not damaged, a relief valve is automatically activated on the released load, thus preventing overweight on the testers or part.

The process carried out by the hardness meter is done to guarantee the resistance of the part and is carried out by penetrating the mechanism of the portable hardness tester and the process can be carried out in all sizes and shapes of parts,

Conclusion

Hardness is a concept with a variety of meanings for different areas and professions. It is defined as resistance to penetration of one hard material into another. It is measured by hardness testers. The portable hardness tester is extremely light and easy to transport. For the use of the portable hardness test it is essential to have a specialized professional. These tester operate by comparing the impressions made on the tested material and on a standard bar of known hardness. Impression is achieved by manually impacting a hammer.

Portable hardness tester is much more flexible and currently much more widespread thanks to the evolution undergone in recent years. Portable hardness testers are used for measuring the hardness of metals. These instruments for hardness tests can be of the Leeb principle, pen or rebound, as well as UCI ultrasonic testers.

All of them are equipped with an external probe. Good testers are mostly certified and are reliable measurements for professional users, laboratories, experimental institutes, industry and production. Numerous reading scales are written on these devices for simultaneous conversion from display of the various measured values.  It is important to remember that hardness is not a physical measure, but a parameter that references the response of a given material to the applied load.