Impact Resistance Testing Service

Advanced Impact Resistance Testing Service – Instrumented, Dynamic, and Multi‑Axial Characterisation for High‑Performance Materials and Critical Applications

For Belgian aerospace, automotive, defence, and civil engineering sectors, where components are subjected to extreme dynamic loads and complex impact scenarios, conventional Charpy and Izod tests are often insufficient to capture the full fracture behaviour. Our ISO/IEC 17025 accredited laboratory offers an advanced impact resistance testing service that goes beyond standard pendulum methods, incorporating instrumented impact, multi‑axial dynamic loading, high‑strain‑rate characterisation, and fracture mechanics under impact. Using state‑of‑the‑art drop‑weight towers, servo‑hydraulic high‑speed test machines, and advanced data acquisition systems, we quantify the dynamic fracture toughness, crack initiation and propagation energies, and the influence of multi‑axial stress states on failure. Our BELAC‑accredited reports are recognised by the Belgian Federal Public Service (FOD Economie), notified bodies, and authorities under the Pressure Equipment Directive (2014/68/EU), the Machinery Directive (2006/42/EC), and the relevant European materials standards (EN ISO 179‑2, ASTM E1820, ISO 12135, etc.).

Instrumented Impact Testing – Force‑Displacement Analysis for Fracture Characterisation

Instrumented impact testing transforms a simple impact energy measurement into a detailed analysis of the entire fracture event, providing separate values for crack initiation and propagation, as well as indicators of ductility and brittleness:

Instrumented Charpy and Izod tests – according to ISO 179‑2 (plastics), ASTM D3763 (plastics), ISO 14556 (metals – instrumented Charpy V‑notch), and NBN EN ISO 14556 – We equip our pendulum impact testers with high‑frequency force sensors (up to 100 kHz sampling rate). The force‑time and force‑displacement curves are recorded during the impact event. From these curves, we determine the yield force (F_y), the maximum force (F_max), the crack initiation energy (E_i), and the crack propagation energy (E_p). The ratio E_p / E_i provides a brittle‑ductile index, which is a powerful tool for material optimisation and quality control.
Instrumented drop‑weight impact test – according to ASTM D3763 (plastics), ISO 6603‑1 (plastics), and EN ISO 6603‑1 – We use a falling‑weight system equipped with a high‑response load cell and a displacement encoder. The force‑deflection curve is recorded at sampling rates up to 1 MHz. We extract the impact force, the energy to peak force, the energy to failure, and the total impact energy. The test is performed at a range of impact velocities (from 1 m/s to 10 m/s) to evaluate the strain‑rate sensitivity.
Dynamic fracture toughness (K_Id) – according to ASTM E1820 (fracture toughness), ISO 12135 (metallic materials – unified method), and EN ISO 12135 – For metals and other linear‑elastic materials, we perform instrumented impact tests on pre‑cracked specimens (e.g., Charpy V‑notch with a fatigue pre‑crack) and calculate the dynamic fracture toughness (K_Id) using the energy method or the force method. This parameter is used in damage‑tolerant design and for the assessment of crack propagation under impact loading.
Impact energy partitioning – we use the force‑displacement curve to separate the total impact energy into the energy absorbed during elastic deformation, plastic deformation, and fracture – This provides a detailed understanding of the energy‑absorbing mechanisms of the material, such as the contribution of cavitation, crazing, or fibre pull‑out in composites.
Strain‑rate sensitivity – we perform instrumented impact tests at different striker speeds (or different drop heights) to determine the strain‑rate sensitivity of the material, expressed as the increase in yield stress and fracture energy per decade of strain rate – This is essential for materials used in high‑speed applications, such as automotive crash components.

Multi‑Axial and Biaxial Impact Testing – Simulating Complex Loading Conditions

In real service, components are often subjected to impact loads from multiple directions, not just uniaxial bending. Our advanced test setups replicate these conditions:

Biaxial impact test – according to ASTM D7766 (for composites), ISO 6603‑2 (plastics – instrumented puncture), and EN ISO 6603‑2 – We clamp a flat specimen in a ring fixture and impact it at the centre with a hemispherical striker. The specimen deforms biaxially (in two directions), which is representative of impact on panels, housings, and automotive body parts. The force‑deflection curve and the failure mode (tear, puncture, or cracking) are recorded.
Dynamic puncture test – for films, foils, and textile composites – using a falling‑weight or pendulum system with a pointed striker (ASTM D3420, ISO 13938‑2) – We measure the energy required to puncture the material and the peak force, which are key parameters for packaging, protective clothing, and membrane applications.
Impact with pre‑applied static load – to simulate a component that is under a service load (e.g., a tensioned conveyor belt, a pressurised vessel) when it receives an impact – We use a servo‑hydraulic test system that applies a static pre‑load (tension, compression, or pressure) and then superimposes an impact load. The dynamic response and the residual strength are measured.
Impact on sandwich structures – to assess the core shear and face sheet interaction – according to ASTM D7766, ISO 18352, and EN ISO 18352 – We impact sandwich panels (e.g., honeycomb or foam core with composite faces) and measure the damage area, the indentation depth, and the residual compression strength after impact (CAI).
Multi‑point sequential impact – to simulate multiple impacts (e.g., debris on a wind turbine blade) – with controlled spacing and energy – We program an automated drop‑weight system to deliver a series of impacts at different locations on the same specimen, measuring the cumulative damage and the propagation of cracks.

High‑Strain‑Rate Tensile and Compression Testing – SHPB and Fast‑Servo

For materials that are subjected to very high deformation rates (up to 10³ s⁻¹), such as in ballistic protection, crash events, and high‑speed forming, we offer specialised high‑strain‑rate testing:

Split‑Hopkinson pressure bar (SHPB) test – according to ISO 26203 (metals – high‑strain‑rate tensile), ASTM E1112 (Hopkinson bar), and EN ISO 26203 – We use a compression or tensile SHPB system to subject a small specimen to a single pulse of very high strain rate (typically 10²‑10⁴ s⁻¹). We measure the stress‑strain curve at this high rate, including the yield strength, the ultimate tensile strength, and the post‑yield behaviour, which are used for the validation of numerical models of impact and crash.
Servo‑hydraulic high‑speed tensile testing – up to 20 m/s – according to ASTM E8 (modified), ISO 6892‑1 (annex), and EN ISO 6892‑1 – We use a fast‑acting hydraulic tester to perform tensile tests at velocities from 0.01 m/s to 20 m/s, covering the intermediate strain‑rate range (1‑100 s⁻¹). The force‑extension curve is recorded with high‑speed data acquisition, and the strain‑rate sensitivity is determined.
High‑strain‑rate compression test – for foams, honeycombs, and crushable materials – according to ASTM D1621 (fast compression), ISO 844 (annex), and EN ISO 844 – We use a drop‑weight or hydraulic fast‑compression system to compress cellular materials at rates typical of crash events, measuring the plateau stress, the densification strain, and the energy absorption per unit volume.
Temperature‑controlled high‑strain‑rate tests – from -40°C to +200°C – using an environmental chamber on the SHPB or fast‑servo system – We condition the specimen and the anvils at the target temperature and perform the high‑rate test to evaluate the combined effect of strain rate and temperature on the flow stress and fracture.

Failure Analysis and Residual Performance After Impact

After an impact event, the material may not be visibly fractured but may contain internal damage that reduces its residual strength. We provide post‑impact characterisation to assess the degree of damage and the remaining service life:

Compression‑after‑impact (CAI) test – according to ASTM D7137 (composites), ISO 18352 (composites), and EN ISO 18352 – We perform a low‑velocity impact on a composite panel, then cut a specimen from the impacted area and subject it to a compression test. The residual compressive strength is compared with the undamaged strength to determine the damage tolerance.
Tension‑after‑impact (TAI) test – for composites and metals – to assess the residual tensile strength after impact – Similar to CAI, but the impacted specimen is tested in tension to evaluate the effect of impact‑induced cracks on the load‑bearing capacity.
Ultrasonic C‑scan and phased‑array inspection – to map the internal damage (delamination, cracks, porosity) non‑destructively after impact – We use ultrasonic scanning to visualise the damaged area, measure the delamination size, and quantify the internal damage, which is correlated with the residual mechanical properties.
Micro‑CT scanning – for high‑resolution 3D visualisation of impact damage, especially for small‑scale specimens and for detecting micro‑cracks – On request, we perform X‑ray computed tomography to reconstruct the 3D damage morphology, providing a detailed picture of the crack network and the debonding interfaces.
Metallographic and fractographic examination – of the damaged area, to identify the failure mechanisms (e.g., cleavage, void growth, intergranular fracture) and to correlate the damage with the impact parameters – We prepare cross‑sections and examine them under an optical microscope or SEM, with EDS analysis if needed.

Environmental and Aging Effects on Impact Performance

Impact properties can degrade significantly due to environmental exposure. We simulate the long‑term effects to predict service life:

UV and weathering conditioning – according to ISO 4892, ASTM G154, and EN ISO 4892 – followed by impact testing – We expose specimens to xenon‑arc or fluorescent UV with water spray for up to 2,000 hours, then perform impact tests to evaluate the loss of toughness due to photo‑oxidation.
Thermal cycling and thermal aging – according to IEC 60068‑2‑14, ASTM E1235, and EN 60068‑2‑14 – We cycle the specimens between -40°C and +120°C (or up to 300°C for metals) for up to 100 cycles, or age them at elevated temperature for up to 1,000 hours, and then test the impact resistance to assess the effect of thermal fatigue.
Salt spray and humid environment – according to ASTM B117, ISO 9227, and EN 60068‑2‑52 – We expose metals and coated materials to salt spray (neutral or acidic) for up to 1,000 hours and then perform impact tests to evaluate the corrosion‑assisted degradation of toughness.
Chemical immersion – according to ASTM D543, ISO 2812 – in acids, bases, oils, or solvents, followed by impact testing – This evaluates the chemical resistance of the material's impact toughness, which is relevant for components used in the chemical and process industries.

Calibration, Traceability, and Data Integrity

All advanced impact tests are performed under our ISO/IEC 17025:2017 accredited quality system, with rigorous calibration and data validation:

Calibration of force sensors and displacement encoders – according to ISO 7500‑1, ASTM E74, and EN ISO 7500‑1 – using certified reference loads and displacement standards – We calibrate each sensor annually, with uncertainties < 0.5% for force and < 0.1% for displacement.
Velocity verification – for falling‑weight and SHPB systems – using a high‑speed camera and a digital timing system (accuracy ±0.1%) – We measure the impact velocity using light barriers or video tracking, and we verify the velocity calculation against a reference.
Data acquisition validation – we test the acquisition system with a calibrated signal generator to ensure the sampling rate and the signal integrity are within specifications – We also perform regular checks of the anti‑aliasing filters and the trigger settings.
Interlaboratory comparison (ILC) – we participate in proficiency testing schemes for instrumented impact, high‑strain‑rate, and fracture toughness testing – Our results are regularly compared with those of other accredited laboratories to ensure consistency.
Reference material testing – we test certified reference materials (e.g., Charpy V‑notch reference steel, certified impact plastics) at the start of each test series to verify the performance of the entire system – The results are plotted on control charts, and any deviation is investigated.

Compliance with Belgian and European Regulations for High‑Risk Components

Our advanced impact testing services directly support the certification and safety verification of critical components under the relevant European directives and Belgian regulations:

Pressure Equipment Directive (PED 2014/68/EU) – for pressure vessels, piping, and valves subject to impact loading – The instrumented Charpy and dynamic fracture toughness (K_Id) tests provide the data required for the design and assessment of fracture‑critical parts, especially at low temperatures.
Machinery Directive (2006/42/EC) – for protective structures, roll‑over protection (ROPS), and falling‑object protection (FOPS) – The multi‑axial impact and CAI tests validate the energy‑absorption capacity and the residual strength of protective structures.
Construction Products Regulation (CPR, EU 305/2011) – for building components such as safety glazing, fall‑through protection, and impact‑resistant wall panels – Our impact tests are performed according to EN 12600, EN 356, EN 13541, and other harmonised standards.
Belgian railway and public works regulations – for impact resistance of components on bridges, tunnels, and railway infrastructure – Our reports are accepted by the Belgian railway authority (Infrabel) and the public works department.

Reporting and Accreditation

All advanced impact tests are performed under our ISO/IEC 17025:2017 accredited quality system, with full traceability of all measurement chains. 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 setup, specimen geometry, and conditioning.
The force‑time and force‑displacement curves (for instrumented tests).
Calculated parameters: impact energy, peak force, crack initiation and propagation energies, K_Id (if applicable), strain‑rate sensitivity.
Post‑impact residual strength (CAI, TAI) and damage area (from ultrasonic or CT scans).
Failure mode and fractographic analysis.
Calibration certificates, measurement uncertainty, and validation against reference materials.
A professional conclusion on the impact resistance and the suitability of the material for the intended application, including recommendations for design or material enhancement.

Our reports provide the confidence you need to certify safety‑critical components and to meet the rigorous demands of Belgian and European regulators.

Why Choose Our Advanced Impact Resistance Testing Service?

We understand that in many applications, the standard impact energy alone is not enough – you need to know how the material behaves during the impact, where the crack starts, how much energy is absorbed in each phase, and what residual capacity remains after the event. Our advanced testing service provides this level of detail, enabling you to optimise materials for energy absorption, damage tolerance, and crashworthiness. We offer rapid scheduling, flexible test programmes (from simple instrumented Charpy to complex multi‑axial and high‑rate tests), and clear, engineering‑focused interpretation of results – we do not just give numbers; we explain the physical mechanisms, the implications for your design, and the potential improvements. We work closely with your finite‑element analysis teams, providing data that directly validates your models and reduces the need for expensive full‑scale testing. With top‑tier equipment, expert analysts, and full accreditation, our advanced impact resistance testing service delivers the depth, accuracy, and regulatory acceptance you need to develop safer, more reliable, and more efficient products for the Belgian and European market. Contact us to discuss your specific impact challenge – we will design a tailored test programme that provides the definitive evidence of your product's performance under dynamic loading.