What Is Erosion?
The erosion test is a test in which solid particles or liquid droplets are sprayed onto the surface at a defined speed and angle while the resulting material loss is measured. It represents the damage mechanism in abrasive-flow environments.
Purpose of Erosion
The purpose is to comparatively determine the resistance of components and protective coatings operating under abrasive flow.
Which Products Is Erosion Applied To?
- Pump and valve components
- Turbine blades
- Pipeline internal surfaces and elbows
- Protective coatings
- Cyclone and conveying-line linings
In Which Sectors Is Erosion Used?
Standards Related to Erosion
- ASTM G76
- ASTM G73
- ASTM G32
Erosion Conditions
- Abradant
- Particle size and material defined in the standard (e.g. alumina)
- Particle velocity
- Fixed speed defined in the specification
- Impingement angle
- Typically 30°, 60° or 90°
- Duration / feed
- Defined as total abrasive quantity or duration
Equipment for Erosion
- Solid-particle erosion tester (nozzle type)
- Abrasive-feed and velocity control system
- Precision balance
- Profilometer or optical measurement
Sample Requirements for Erosion
- The specimen surface must be flat and clean
- Initial mass must be measured on a precision balance
- Thickness must be recorded for coated specimens
- Generally at least three specimens
Duration of Erosion
It depends on the feed quantity. A typical test takes a few hours.
Erosion Procedure
- 1The specimen surface is prepared and its mass is measured.
- 2Abradant type, velocity and impingement angle are set.
- 3The defined quantity of abradant is sprayed.
- 4The specimen is cleaned and its mass is remeasured.
- 5The erosion rate is calculated and the crater profile is taken.
Erosion Acceptance Criteria
The acceptance criterion is given in the specification as a maximum mass loss or a maximum erosion rate.
Evaluation of Results
The erosion rate depends strongly on the impingement angle: ductile materials lose more at shallow angles, brittle materials at steep angles. The angle must therefore always be stated in the report.
Erosion Report
- Standard applied
- Abradant type, particle size and quantity
- Particle velocity and impingement angle
- Mass loss and erosion rate
- Crater profile and images
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
- Oil and gas equipment specifications
- Power-plant component standards
Mekanik Testler — What Does This Testing Field Cover?
The section below describes the field that the Erosion 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.
Mechanical testing measures how a material or a part behaves under force. The family ranges from static loading (tension, compression, bending) to time-dependent behaviour (fatigue, creep), and from hardness and wear to fracture toughness.
What these tests have in common is that the result is reported as a MATERIAL PROPERTY. Yield strength or hardness is not a conformity decision; it is numerical data against which the design and the product standard will compare. Mechanical test reports are therefore usually an input to an engineering decision rather than to a product approval — material selection, safety factor, life prediction.
The distinction between static and dynamic behaviour is the key to understanding the field. A part may appear entirely unstressed under a static load yet break under repeated loading; fatigue fracture occurs at stresses well below the yield strength and gives no warning. For rotating, vibrating or cyclically loaded parts, a tensile test alone is therefore not sufficient evidence.
Test conditions determine the result, and this is critical for the readability of the report: specimen geometry, loading rate, temperature, conditioning and the gripping arrangement. The same material gives different values under different conditions. In plastics the rate effect is very pronounced, in metals the temperature effect; in composites the specimen orientation changes the result entirely.
Hardness is the most misused measurement in the field. Because it is fast, close to non-destructive and inexpensive, it is often used in place of strength. Conversion tables from hardness to strength exist, but they are APPROXIMATE and depend on the material group; using them as the sole evidence in material acceptance is wrong.
The fracture mechanics side requires a specific competence. Fracture toughness and fatigue crack growth rate measurements make it possible to calculate how long a cracked structure will last; they are the basis of damage-tolerant design in fields such as pressure equipment, aircraft structures and pipelines.
Method groups in this field
Static tests
Tension, compression, bending, shear and torsion. Yield and tensile strength, elongation and modulus of elasticity are obtained.
Impact tests
Charpy and Izod notch impact; the brittle-to-ductile transition behaviour of the material is determined as a function of temperature.
Hardness
Brinell, Vickers, Rockwell, Shore and micro hardness. Valuable for surface treatment depth and local differences in strength.
Fatigue
Force- and strain-controlled axial fatigue, fatigue in bending; S-N curves and the endurance limit.
Creep and stress relaxation
Behaviour under long-term load at high temperature; decisive for boiler, turbine and pressure equipment materials.
Fracture mechanics
Plane-strain fracture toughness, the J integral, CTOD and fatigue crack growth rate.
Wear and friction
Taber and rotating drum abrasion, coefficient of friction measurements.
Commonly confused in this field
- Calculating strength from hardness is approximate; it cannot be used as the sole evidence in material acceptance.
- Adequate static strength does not demonstrate fatigue strength; a cyclically loaded part requires a separate test.
- If test rate and temperature are not reported, the result cannot be compared — especially for polymers and composites.
- A test specimen and the actual part may not give the same value; moulding orientation, weld lines and differences in surface treatment all have an effect.
- A strength value given for a composite without stating the specimen orientation is meaningless.
- ASTM and ISO counterparts measure the same quantity but use different specimen geometries; the results are not treated as directly equivalent.
Which decisions these results support
- Design verification and material selection
- Incoming material control and supplier approval
- Meeting the mechanical requirements of the product standard
- Failure analysis, life prediction and damage tolerance calculation
- Verifying heat treatment and surface treatment processes
Related Tests
Frequently Asked Questions About Erosion
According to which standard is Erosion made?
Erosion is executed in scope ASTM G76, ASTM G73 and ASTM G32. 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 Erosion apply to?
Mainly applied to Pump and valve components, Turbine blades, Pipeline internal surfaces and elbows, Protective coatings and Cyclone and conveying-line linings. Whether your product is included in the scope is determined by examining its technical specifications and intended use.
Under what conditions is Erosion done?
The determining parameters are: Abradant — Particle size and material defined in the standard (e.g. alumina), Particle velocity — Fixed speed defined in the specification and Impingement angle — Typically 30°, 60° or 90°. 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 Erosion?
The specimen surface must be flat and clean, Initial mass must be measured on a precision balance and Thickness must be recorded for coated specimens. The number of samples is determined according to the product standard and the scope to be reported.
How long does Erosion take?
It depends on the feed quantity. A typical test takes a few hours. 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 Erosion result called "appropriate"?
The acceptance criterion is given in the specification as a maximum mass loss or a maximum erosion rate.