Hardness Testing

The hardness test is the most widely used test for evaluating the mechanical properties of metals and other materials. Acuren’s team is trained in field hardness testing, producing immediate results without damage to your components. The purpose of the hardness test is to determine the suitability of a material for a given application, conformance to a specification, standard, or particular treatment to which the material has been subjected (heat treatment, thermal process). Our team is expertly trained to perform  hardness training for every industry sector including:

• Off-shore
• Pipeline
• Oil & gas
• Structural
• Manufacturing
• Aerospace
• Agriculture
• Mining
• Pulp & paper
• Nuclear
• Power generation, and more

Hardness testing for new and in-service components

Hardness testing is typically performed on new components but can also be used on in-service components to identify any  issues. Hardness testing can reveal susceptibility to cracking as a result of exposure to environmental constituents such as hydrogen sulphide. It can also identify degradation and softening as a result of exposure to elevated temperatures (e.g. fire damage). For some metals, hardness test results can be used to estimate the material’s tensile strength, using ASTM E140 Conversion tables.

Field Hardness Testing

Portable hardness testing devices were developed because  bringing a stationary Brinell, Rockwell or Vickers tester to the field was impractical . In addition, it is not always practical to cut samples from a component to have hardness testing performed under controlled laboratory conditions.

Why choose Acuren for your portable hardness testing?

Highly qualified technicians

At Acuren, hardness testing is performed by only experienced technicians who are qualified to Acuren procedures, industry standards, and client specifications to obtain reliable, precise measurements. There are several variables that affect the accuracy and repeatability of hardness testing performed in the field including:

• The operator
• Surface condition
• Material geometry
• Material thickness
• Metallurgy

Each of these variables must be considered when selecting the appropriate test method,  and the Acuren team has the knowledge and experience to get the job done right.

Immediate, accurate results

Acuren can provide on-the-spot results followed by the certification of results in a written report.  We also interpret and advise on the results. Acuren’s responsive turnaround times ensure that we meet our client’s operational schedules and if further analysis is required, we can provide laboratory testing to corroborate findings. Our clients can be assured of rapid, reliable service with accurate results that will help to ensure your products meet the required industry safety and quality standards.

Full-service testing and analysis

Acuren is able to follow-up the field hardness testing with a full spectrum of laboratory services including mechanical testing, metallurgical testing, and chemical analysis. Field hardness testing is often performed  with metallurgical replication as part of a fitness-for-service analysis or fire investigation. With our in-house team of trained experts,  hardness testing process is more streamlined and more cost effective for your team.

Industry Need For Hardness Testing

Hardness testing is typically performed in the field as a quality control measure to ensure a material meets a client’s specification, material specification, standard or code. These specifications are typically in the form of a specified minimum value, maximum value, or allowable range.

• For owners, if materials are supplied with improper hardness levels, it can be very costly and can even result in catastrophic failures. Hardness testing is performed at various stages in the life-cycle of equipment from the initial manufacturing, post-welding, post-erection, and in-service.
• To ensure various steel and alloy materials have received the required heat treatment post-fabrication
• To determine if there has been significant  strength reduction  on materials in-service as a result of exposure to elevated temperatures

Hardness testing is a key aspect in quality control programs for new construction projects to ensure the materials are supplied in the required condition.

Test Methods Available

MicroDur Hardness Testing: Determination of hardness of metallic materials by the Ultrasonic Contact Impedance (UCI) method, as specified in ASTM A1038, is done using the MicroDur series of hardness testers. The UCI method uses a Vickers diamond indenter, allowing for precise placement of the indent and resulting in a highly localized hardness test. But unlike in conventional Vickers testing, the reading is not derived through optical measurement of the test indentation. Instead, the indentation area is detected by electronically measuring the shift in an ultrasonic frequency that occurs when the load is applied. Because of the small footprint of the Vickers diamond, it is quite effective at measuring the hardness in a heat-affected zone, and up to the toe of a weld. Other portable testers have a larger footprint and this limits their ability to measure in this area. It is also an excellent tool for looking at the hardness of gear teeth due to the small impression. This method requires the most surface preparation as compared to other methods.

Brinell Hardness Testing: Acuren performs both Shear Pin and Telebrinell methods of testing for determining the macrohardness of metallic samples. Telebrinell tests are covered by ASTM A833, however, the Shear Pin test method is not covered under an ASTM standard at this time. The Shear Pin and Telebrinell tests utilize a three-pound hammer to supply the load required for creating a round impression on the workpiece. The diameter of the indentation is then measured optically, and this value is then converted to a Brinell hardness number using a formula or chart. This method requires less surface preparation than microhardness testing, although it cannot be used to measure the hardness in smaller areas such as the hardness in a narrow heat affected zone of a weld.

Leeb Hardness Testing: Determination of hardness on metallic materials by the Leeb rebound method, as specified in ASTM A956, is another method for determining hardness. In this method, a tungsten carbide ball is propelled against the test surface, the rebound velocity relative to the incident velocity is measured and converted to a Leeb hardness (LB). The harder the test material, the faster the rebound, and the higher the hardness value. A variety of impact devices are available to suit a range of testing applications, but in general this instrument is best suited for use on thicker solid parts like castings and forgings.

Barcol Hardness Testing: Determination of the hardness of both reinforced and non-reinforced rigid plastics, as specified in ASTM D2583, is done with a Barcol hardness tester. The specimen is placed under the indenter of the Barcol hardness tester and a uniform pressure is applied to the specimen until the dial indication reaches a maximum. The depth of the penetration is converted into absolute Barcol hardness value.

Shore Durometer Hardness Testing: Hardness testing of polymeric materials, including plastics and rubbers, is performed by the Shore Durometer Test, according to ASTM D2240. This method determines a material’s hardness value or resistance to indentation by penetration of an indenter into the test sample. Because the flexibility of polymers varies considerably, instruments are equipped with various indenters for use in testing different types of materials from elastomers to rigid plastics. The Shore A scale is used for ‘softer’ rubbers while the Shore D scale is used for ‘harder’ ones; other scales are available but less commonly used.