What Is Impact Resistance?
Coating impact resistance test is performed in which a defined mass is dropped onto the coated panel from a certain height; It is the test that evaluates whether there is any cracking, breaking or separation from the lower surface in the impact area.
Purpose of Impact Resistance
The aim is to verify that the coating maintains its flexibility and adhesion against sudden mechanical impact.
Which Products Is Impact Resistance Applied To?
- Coated sheet and panel products
- Powder coated parts
- Automotive paint systems
- White goods coatings
In Which Sectors Is Impact Resistance Used?
Standards Related to Impact Resistance
- ISO 6272-1
- ISO 6272-2
- ASTM D2794
- ISO 6860 (tilt pulse)
Impact Resistance Conditions
- falling weight
- Mass and impact tip geometry defined in the standard
- Altitude
- The damage threshold is determined by gradually increasing; energy is given in joules
- Assessment
- Cracking, separation; by cross-cutting or tape testing if necessary
- Temperature
- Defined in the specification; low temperature pulse may also be requested
Equipment for Impact Resistance
- Falling weight impact tester
- Calibrated mass and impact tips
- Coating-thickness gauge
- Magnifying glass and tape testing material
Sample Requirements for Impact Resistance
- Panel bottom material and thickness must comply with the specification
- Coating thickness must be measured
- The panel must be firmly supported
- Conditioning and temperature condition must be documented
Duration of Impact Resistance
Typically 1–3 days.
Impact Resistance Procedure
- 1The panel is conditioned and the thickness is measured.
- 2The mass and impact tip are selected.
- 3Impact is applied at gradual heights.
- 4Impact areas are examined with magnification.
- 5If necessary, separation is evaluated with a band test.
- 6The highest energy without damage is reported.
Impact Resistance Acceptance Criteria
The acceptance criterion is the absence of cracking and separation at the minimum impact energy given in the specification.
Evaluation of Results
The result depends more on the thickness and support of the substrate than on the coating; If the panel changes, the value changes. For this reason, the results cannot be compared without writing the sub-material definition into the report.
Impact Resistance Report
- Standard applied
- Substrate material and coating thickness
- Mass, tip of impact and heights
- Temperature and conditioning
- Damage findings and energy consumed
Accreditation
EUROLAB holds internationally recognised accreditation obtained from accreditation bodies party to the IAF and ILAC multilateral recognition arrangements, under ISO/IEC 17025 for laboratory testing, ISO/IEC 17020 for inspection and surveillance, and ISO/IEC 17021-1 and ISO/IEC 17065 for system and product certification. This chain ensures the reports and certificates issued are accepted worldwide.
Whether this test can be offered within accredited scope depends on your product and the standard applied; since accreditation is method-based, the scope is confirmed in writing at the quotation stage.
Scope and authorisationsRelated Regulations
- Paint and coating specifications
Paint and Coating Testing — What Does This Testing Field Cover?
The section below describes the field that the Impact Resistance test belongs to; the conditions and acceptance criteria of this particular test are given in the sections above. The scope specific to your product is confirmed in writing at the quotation stage.
Paint and coating testing measures the adhesion of a coating to the surface, its mechanical durability and its resistance to environmental effects. Because a coating is a thin layer, the results depend both on the material and on the QUALITY OF APPLICATION; the same paint gives an entirely different result over a different surface preparation.
This dual dependence is the most important knowledge in the field. A coating failure usually arises not from the paint itself but from the surface preparation: oil residue, insufficient roughening, an oxide layer or moisture. Coating tests therefore assess not only the product but also the process, and the results are used for process control.
COATING THICKNESS is a recurring variable in the field. Many durability results relate directly to thickness; a thin area becomes the starting point of corrosion. Thickness measurement is therefore reported routinely alongside the other tests and is usually taken at several points — thickness falls at edges and corners, especially on complex geometries.
Three approaches are used on the adhesion side, each giving different information. The tape test is fast and suitable for field use but is a coarse scale. The cross-cut test shows behaviour at the intersections of layers. The pull-off method produces a numerical strength value and is the most suitable for comparison.
On the mechanical side, flexibility (mandrel bending), impact resistance, hardness, abrasion and stone chip resistance are measured. Stone chipping has a special place in automotive: gravel striking the coating under real road conditions is simulated, and the result is assessed according to whether the coating continues to protect the base metal.
On the appearance side, gloss and colour difference are monitored NUMERICALLY. Colour is assessed with a colour measuring instrument rather than by eye and the colour difference is expressed as a number; this makes it possible to compare different lots and different suppliers.
On the durability side, accelerated ageing (xenon arc, fluorescent UV), humidity, condensation and salt spray are applied. The result is assessed with scales for blistering, rusting, creep from a scribe and loss of adhesion; these scales are defined in separate standards and the report must state which was used.
In industrial processes such as powder coating and electrophoretic coating, the curing cycle (temperature and time) is what determines the result. An under-cured coating looks good but has poor chemical resistance and adhesion; oven profile measurement is therefore part of coating quality control.
Method groups in this field
Thickness
Dry film thickness by magnetic and non-magnetic methods; multi-point measurement and assessment of the distribution.
Adhesion
Tape test, cross-cut test and pull-off adhesion strength.
Mechanical strength
Mandrel bend flexibility, rapid deformation (impact), pencil and scratch hardness, Taber abrasion, stone chipping.
Appearance
Gloss measurement, colour difference calculation, orange peel and surface defect assessment.
Environmental durability
Salt spray, humidity, condensation, xenon arc and fluorescent UV ageing, chemical and stain resistance.
Assessment scales
Scales for blistering, degree of rusting, creep from a scribe and loss of adhesion.
Commonly confused in this field
- A coating result depends on the surface preparation; even if the paint itself is good, a poor preparation gives a poor result.
- A durability result without a reported thickness cannot be compared.
- The tape test is a coarse scale; numerical comparison requires the pull-off method.
- Colour cannot be assessed by eye; numerical colour difference measurement is required.
- An ageing result without a stated assessment scale cannot be interpreted.
- If the curing cycle is incomplete the coating looks good but its durability is poor; the oven profile is part of quality control.
Which decisions these results support
- Paint system approval and supplier selection
- Process control of the paint line and lot acceptance
- Supporting outdoor and automotive durability claims
- Detecting defects arising from surface preparation
- Monitoring colour and gloss consistency lot by lot
Related Tests
Frequently Asked Questions About Impact Resistance
According to which standard is Impact Resistance made?
Impact Resistance is executed in scope ISO 6272-1, ISO 6272-2, ASTM D2794 and ISO 6860 (tilt pulse). The limit values and acceptance criteria to be applied are defined in the product standard; The version valid for your product is confirmed in writing at the offer stage.
Which products does Impact Resistance apply to?
Mainly applied to Coated sheet and panel products, Powder coated parts, Automotive paint systems and White goods coatings. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is Impact Resistance done?
The determining parameters are: falling weight — Mass and impact tip geometry defined in the standard, Altitude — The damage threshold is determined by gradually increasing; energy is given in joules and Assessment — Cracking, separation; by cross-cutting or tape testing if necessary. The full terms are in the "Test Conditions" section on the page and vary depending on the product standard.
What kind of sample is needed for Impact Resistance?
Panel bottom material and thickness must comply with the specification, Coating thickness must be measured and The panel must be firmly supported. The number of samples is determined according to the product standard and the scope to be reported.
How long does Impact Resistance take?
Typically 1–3 days. This duration belongs to the experiment itself; sample preparation, queuing and reporting are also evaluated. A realistic schedule for your product is given in the offer.
What is the Impact Resistance result called "appropriate"?
The acceptance criterion is the absence of cracking and separation at the minimum impact energy given in the specification.