Hardness Testing Services

Brinell test ASTM E10 and ISO 6506-1

The oldest hardness method still in common use. The Brinell instrument employs a larger indentor ball (typically 10mm in diameter) and a much higher load (up to 3,000 kgf) than most other test methods for hardness.

The larger indenter helps ensure that hardness readings are not adversely affected by small surface flaws. Because of this, Brinell scale testing is frequently used on rough materials with a large number of surface imperfections, such as castings and forgings. The most common industry standards for Brinell hardness are ASTM E10 and ISO 6506-1.

Rockwell test ASTM E18 and ISO 6508-1

Generally considered to be the most popular  of all hardness methods. Using a ball or cone-shaped indentor, Rockwell hardness is used on metals of all types, except for any material with an irregular structure or surface variations that might influence test results.

The Rockwell method, which is detailed in ASTM E18 and ISO 6508-1, involves the use of a diamond indenter to apply a smaller preload on the material. This preload breaks through the material’s surface to eliminate the effects of any surface treatments. After the preload, the major load is applied to complete the test giving a direct reading from the instrument negating the need to measure the indent.

Knoop hardness ISO 4545 and Vickers hardness test ASTM E384 and ISO 6507-1

Two of the most common scales of microhardness. These tests use light loads and small indenters, making them ideal for small samples, very thin materials, surface coatings, or for evaluating the case hardness of a material through a series of indentations that create a hardness profile.

In accordance with ASTM E384, the Vickers hardness method utilizes a pyramid-shaped diamond indenter. In Knoop microhardness, the indenter is rhombic-pyramid-shaped for longer, shallower indentations.

Element’s metallurgical laboratories are equipped with advanced microhardness testing equipment as well as all the tools necessary to provide expert sample preparation services, including sectioning, mounting, polishing, and etching.

Hot hardness testing

Measures material hardness while at elevated temperature. Hot hardness can be valuable for assessing and comparing materials, such as tool steels and wear resistant coatings, which are used in high temperature applications such as valve seats and dyes. 

Element conducts hot testing similarly to normal Vickers hardness testing, except that the test is conducted inside a vacuum chamber which is capable of providing an elevated temperature of up to 1,600F.

Shore hardness testing to ASTM D2240, ISO 7619, and ISO 868 

Are performed on rubbers and elastomers as well as “soft” plastics like vinyl and fluoropolymers. This test uses a piece of equipment called a Durometer, which consists of a calibrated spring and a cone-shaped or sphere-shaped indenter foot.

Because of the unique properties of plastics and elastomers, Shore hardness values often vary depending upon the amount of time the force is held. It is also not advisable to correlate Shore hardness results with other material properties.  

Barcol hardness testing to ASTM D2583

A popular industrial test method thanks to the simplistic and portable nature of the Barcol instrument. This penetration test uses a sharp steel point under a spring load, which is pressed against a flat surface of the material. The hardness of the material is determined based on the depth that the tip penetrates in comparison to a reference material.

The Barcol impressor was developed by Walter Colman to allow the US Army Air Corps to field test the hardness of rivets during World War II, due to concerns that aircrafts might be sabotaged by replacing normal rivets with soft lead or wooden ones. 

Today, Element’s experts mainly utilize this method in conjunction with glass transition temperature measurements to indirectly determine the cure of a composite or epoxy material. Other uses include in-lab and field hardness measurements of both reinforced and non-reinforced rigid plastics as well as very soft metals, such as aluminum, brass, copper, and lead.

Vicat Softening Point / Vicat Softening Temperature (VST) ASTM D1525

Determines the softening point for materials that have no definite melting point, such as plastics. It is a measure at which an indenter penetrates the specimen to a certain depth under a standardized loading using a steady temperature rise.

The high-temperature physical properties of plastics and polymers can be observed using the Vicat Softening tests as Polymers can still withstand loads of temperatures over 200C while other polymers can fail to reach loads at 100C. Our VST tests help you predict the behavior of a material and its ability to retain surface properties at high temperatures.

Element performs Vicat Softening Temperature tests according to international standards and procedures, including ISO 21809, ISO 306, EN 1028, and ASTM D1525. Our VST testing capabilities include materials such as coatings, polymers, composites, cement, and plastics.