Fuel permeability testing service

Surface Vickers Hardness Testing Service – Accredited Micro‑Indentation Hardness Measurement for Thin Coatings, Surface‑Treated Layers, and Small Components

For Belgian manufacturers, metallurgists, and quality engineers in the automotive, aerospace, tooling, electronics, and medical device industries, the surface hardness of a component – whether a thin coating, a diffusion‑hardened layer, a nitrided surface, or a miniature precision part – is a critical parameter that determines wear resistance, load‑bearing capacity, and service life. Our ISO/IEC 17025 accredited laboratory offers a specialised surface Vickers hardness testing service that provides accurate, reproducible hardness measurements on surfaces, cross‑sections, and micro‑scale features using state‑of‑the‑art micro‑indentation and nano‑indentation equipment. With test forces ranging from 1 gf (0.0098 N) to 1 kgf (9.8 N) and beyond, we can characterise the hardness of coatings from a few micrometres to several millimetres thick, as well as the hardness gradient across case‑hardened layers. Our BELAC‑accredited reports are recognised by the Belgian Federal Public Service (FOD Economie), notified bodies, and authorities under the Machinery Directive (2006/42/EC), the Pressure Equipment Directive (2014/68/EU), and the relevant harmonised standards (ISO 6507, ASTM E384, EN ISO 6507, etc.).

Specimens and Applications We Regularly Test

We accept a wide variety of specimens, from flat polished sections to curved or irregularly shaped components. Our hardness testers are equipped with precision anvils, clamping fixtures, and positioning stages to accommodate different geometries and test locations. Common samples include:

Thin coatings and plated layers – electroplated nickel, chrome, zinc, and tin; electroless nickel; anodic oxide layers; and painted or powder‑coated surfaces.
Hard coatings – PVD, CVD, DLC, TiN, TiAlN, CrN, and diamond‑like carbon coatings.
Thermochemical surface treatments – carburised, nitrided, carbonitrided, boronised, and induction‑hardened case layers.
Small precision components – gears, springs, bearings, pins, and needles.
Metallographic cross‑sections – for measuring the hardness profile across case depth, weld zones, or graded structures.
Brittle and ceramic materials – where large‑force indentation would cause fracture.
Medical implants and devices – titanium, cobalt‑chromium, stainless steel, and ceramic components.
Additively manufactured components – for assessing the surface hardness of laser‑melted or electron‑beam‑melted parts.

Core Test Methods – Vickers Micro‑Indentation and Nano‑Indentation

Our surface Vickers hardness testing service follows the most recognised international standards, with Belgian NBN implementations, to provide reliable and comparable hardness values. The Vickers principle uses a square‑based diamond pyramid indenter (136° included angle) and measures the diagonal length of the resulting indentation to calculate the hardness:

Vickers hardness test (HV) – according to ISO 6507‑1, ASTM E384, and NBN EN ISO 6507‑1 – We apply a test force ranging from 0.098 N (HV 0.01) to 9.8 N (HV 1) using a precision micro‑hardness tester equipped with a diamond indenter and a high‑magnification optical measurement system (or an automated image analysis system). The test force is maintained for a specified dwell time (typically 10‑15 seconds). The two diagonals of the indentation are measured, and the Vickers hardness (HV) is calculated from the ratio of the test force to the indentation surface area. We perform multiple indentations (typically 5‑10) per specimen to obtain a statistically reliable average.
Knoop hardness test (HK) – according to ISO 4545, ASTM E384, and NBN EN ISO 4545 – As an alternative to Vickers, we use the Knoop indenter (a diamond with an elongated pyramidal shape) for very thin coatings (< 10 µm) or for anisotropic materials, where the Vickers indentation would be too deep or would produce a different result depending on the orientation. The test force is typically lower (0.0098 N to 1.96 N), and the hardness is calculated using the projected area of the indentation.
Vickers hardness profile (case depth measurement) – according to ISO 6507‑1 (annex for case depth) and EN ISO 6507‑1 – For carburised, nitrided, or induction‑hardened layers, we perform a series of indentations along a line perpendicular to the surface (either on a cross‑section or by making indentations at progressively increasing distances from the surface). We plot the hardness (HV) vs. depth and determine the effective case depth (the depth at which the hardness drops to a defined value, e.g., 50 HRC equivalent or a specified HV value).
Measurement of indentation diagonals – using an optical microscope with a digital camera and image analysis software (ASTM E384, ISO 6507) – We measure both diagonals to within 0.1 µm, and we check the symmetry of the indentation to ensure that the test was properly performed. Any indentations that are asymmetric or that show cracks or edge effects are discarded.
Force and time calibration – we verify the test force using certified calibration weights (or a calibrated load cell) and the dwell time using a calibrated timer, ensuring that the test conditions are within the tolerances specified in the standards – The indenter geometry is also checked periodically using a certified reference block.

Specimen Preparation and Surface Quality

Accurate Vickers hardness measurement requires a well‑prepared surface with a defined finish and minimal deformation. We provide full specimen preparation services to ensure that the test results are not affected by surface defects:

Metallographic preparation – we cut, mount, grind, and polish the specimen to achieve a flat, scratch‑free surface with a roughness Ra < 0.2 µm (preferably < 0.1 µm) – The polished surface is examined under a microscope to ensure that it is free of embedded particles, smearing, or other artifacts that could interfere with the indentation measurement.
Cross‑section preparation – for measuring hardness profiles on thin coatings or case‑hardened layers, we mount the specimen in resin and prepare a polished cross‑section that is perpendicular to the surface – The cross‑section is etched (if required) to reveal the microstructure, and the hardness is measured at defined distances from the surface.
Surface cleaning – we clean the specimen with an ultrasonic bath in ethanol or a suitable solvent to remove any oil, dust, or residual polishing compounds – A clean surface is essential for precise indentation measurement.
Thickness measurement – for coatings, we measure the coating thickness (using a calibrated microscope or a coating thickness gauge) and ensure that the indentation depth does not exceed 10% of the coating thickness (to avoid substrate influence) – If the coating is too thin, we recommend the Knoop method or a nano‑indentation technique.
Edge and corner mounting – for small or irregularly shaped specimens, we use specialised clamping fixtures that hold the specimen securely without deforming the test area – We ensure that the indentation is made on a flat, stable surface.

Advanced Testing – Micro‑Hardness Profile, Thin Coating, and Nano‑Indentation

For ultra‑thin coatings, graded layers, or very localised hardness measurements, we offer advanced techniques that extend the range of conventional Vickers testing:

Micro‑Vickers hardness mapping – we use a motorised XY stage and automated indentation to create a hardness map of a defined area (e.g., across a weld, a heat‑affected zone, or a gradient layer) – We generate contour plots and statistical summaries that reveal the uniformity (or lack thereof) of the surface hardness.
Nano‑indentation (instrumented indentation) – according to ISO 14577, ASTM E2546, and EN ISO 14577 – For coatings with a thickness below 1 µm or for very localised measurements, we use a nano‑indenter that continuously records the load and displacement during the indentation cycle. We determine the hardness (H) and the indentation modulus (E) from the load‑displacement curve. This method is particularly useful for evaluating the surface hardness of thin films without substrate interference.
Selective and site‑specific hardness measurement – we use a high‑magnification optical system to target specific micro‑phases, inclusions, or other features (e.g., the hardness of a particular grain, a carburised layer, or a hard particle within a matrix) – This is essential for failure analysis and for understanding the relationship between microstructure and hardness.
Low‑load Vickers (HV 0.01 – HV 0.05) – for very thin coatings and soft materials, we use the lowest test forces to minimise penetration and to obtain an accurate measure of the surface hardness without substrate effects – We carefully check the indentation size (which may be less than 10 µm) and use a calibrated microscope with a high‑magnification objective.
Step‑wise testing along the depth – we perform a series of indentations at increasing distances from the surface (e.g., at 10 µm intervals) to generate a hardness‑depth profile – This is used to determine the effective case depth and the uniformity of the hardening.

Evaluation Criteria and Reporting – Presenting Clear, Actionable Hardness Data

We provide not only the numerical hardness values but also a comprehensive interpretation that supports your material selection, quality control, and failure analysis:

Conversion to other hardness scales – we provide equivalent values on the Rockwell, Brinell, or Shore scales, based on standard conversion tables (ASTM E140, ISO 18265), if required – This is useful for direct comparison with your design specifications or supplier data.
Statistical analysis – we calculate the mean, standard deviation, minimum, maximum, and coefficient of variation for each set of hardness measurements – We also report the measurement uncertainty, based on the variability of the indentation diagonals.
Comparison with specification or target – we compare the measured hardness with your specified requirement (e.g., a minimum HV value) and give a clear pass/fail conclusion – We also provide graphical representation (e.g., a hardness profile plot) to illustrate the distribution of hardness values.
Fracture and failure analysis – when hardness values are outside the expected range, we investigate possible causes, such as incorrect heat treatment, contamination, decarburisation, or surface defects – We examine the indentation morphology (e.g., cracks, edge chipping) for additional clues.
Advice on process optimisation – based on the hardness results, we recommend adjustments to the heat treatment, coating process, or surface preparation to achieve the required hardness or uniformity – For example, we suggest changes to the carburising time or the quenching temperature to increase or decrease the surface hardness.

Calibration, Accuracy, and Quality Assurance

All Vickers hardness tests are performed under our ISO/IEC 17025:2017 accredited quality system, with full traceability of force, indenter geometry, and measurement:

Calibration of the test force – we verify the force using certified calibration weights (class E1) or a calibrated load cell, with uncertainty < 0.5% – The force is checked at multiple test force levels.
Calibration of the indenter – we use certified reference hardness blocks (HV 100, HV 300, HV 700, etc.) to verify the indenter geometry and the overall system performance – We check the indentation size and shape on the reference block, and we adjust the measurement system if any deviation is detected.
Calibration of the measuring microscope – we use a certified stage micrometer to calibrate the magnification and the pixel resolution, ensuring that the diagonal measurement is accurate to within ±0.1 µm – The microscope is calibrated at the start of each test series.
Verification with reference blocks – we test certified reference hardness blocks at regular intervals to confirm the stability of the test system – The results are tracked on control charts and must be within the specified tolerance limits.
Interlaboratory comparison (ILC) – we participate in proficiency testing schemes for hardness testing (Vickers, Knoop, and micro‑hardness) – Our results are regularly compared with those of other accredited laboratories.

Compliance with Belgian and European Regulations

Our surface Vickers hardness testing services support your conformity assessment under the relevant European directives and Belgian regulations for machinery, pressure equipment, and quality management:

Machinery Directive (2006/42/EC) – for components subject to wear, friction, or high contact stresses (e.g., gears, bearings, camshafts) – The surface hardness is a critical design parameter for ensuring wear resistance and pitting life.
Pressure Equipment Directive (PED 2014/68/EU) – for pressure‑containing components that require surface hardening to resist erosion or galling – Hardness testing verifies that the surface treatment has been applied correctly.
Medical Devices Regulation (EU 2017/745) – for orthopaedic implants and surgical instruments – Surface hardness is often part of the essential requirements for wear resistance and biocompatibility.
Belgian national regulations – including the ARAB (General Regulation on Occupational Safety) for lifting and handling equipment – Our reports are used to verify the quality of surface‑hardened components used in safety‑critical applications.

Reporting and Accreditation

All Vickers hardness tests are performed under our ISO/IEC 17025:2017 accredited quality system, with full traceability of all measurement parameters. Our BELAC‑accredited reports are recognised by the FOD Economie, Belgian notified bodies, and European authorities. Each report includes:

A complete description of the test specimen (material, surface condition, preparation method).
The test method and conditions (test force, dwell time, number of indentations).
The measured hardness values (HV or HK) for each indentation, with the average, standard deviation, minimum, maximum, and coefficient of variation.
For profile measurements, a table and a graph of hardness vs. depth, with the effective case depth indicated.
Images of the indentation (if requested) to document the measurement quality.
Calibration certificates and measurement uncertainty statements.
A professional conclusion on the surface hardness and its conformity to the specified requirement, with recommendations for improvement if necessary.

Our reports provide the confidence you need to certify your heat‑treated, coated, or surface‑engineered components, to approve deliveries, and to meet the quality standards of the Belgian and European market.

Why Choose Our Surface Vickers Hardness Testing Service?

We understand that surface hardness is often the key to the performance and durability of components subjected to wear, friction, and contact fatigue. Our service provides the precise, reliable data you need to verify your heat treatment, to validate your coating processes, and to ensure the quality of your finished parts. We offer rapid scheduling, flexible specimen handling (from small pins to large panels), and clear, practical interpretation of results – we do not simply give you a hardness number; we explain the significance of the result, the possible causes of any deviations, and the actions you can take to achieve the required hardness. We work closely with your metallurgists, process engineers, and quality managers to design a test programme that matches your specific material and application. With state‑of‑the‑art micro‑hardness testers, high‑resolution optical systems, and a highly experienced team, our surface Vickers hardness testing service delivers the accuracy, repeatability, and regulatory acceptance you need to ensure the quality and reliability of your surface‑treated components. Contact us to discuss your materials, your hardness requirements, and your certification goals – we will develop a tailored test programme that provides the definitive assessment of your surface hardness.