Abrasion Resistance Testing

Industry Impact, Methods, Abrasion Testers, Affecting Factors, and Application

Abrasions resistance testing is a critical aspect of material science and engineering, encompassing a range of test methods aimed at evaluating a material's ability to withstand wear and erosion caused by repeated mechanical contact with abrasive surfaces. By subjecting materials to controlled mechanical forces, these tests simulate real-world conditions to assess their resistance to abrasion and wear. All testing with this type of equipment involves moving one surface with respect to another under controlled conditions and determining any resulting change or interaction between the surfaces.

Abrasion testing is also used to test the washability or scrubability of coatings and other surfaces. Both coated and uncoated surfaces need to be tested for abrasion resistance by sandpaper, brush, sponge, or other means and can be tested by wet abrasion methods using scrub media or cleaning solutions. This article describes the impact, common test methods, types of abrasion testers, affecting factors and common applications used in industry.

Impact of Abrasion Resistance Testing

Abrasion resistance testing is of utmost importance in industries such as manufacturing, construction, automotive, aerospace, and textiles, where materials are subjected to various levels of wear and tear during their operational life. Abrasion resistance testing plays a pivotal role in assessing a material's durability and performance under real-world conditions. It is critical in the material selection, quality control and research and development for quality products.

• Material selection:Engineers and designers rely on abrasion resistance testing to select appropriate materials for specific applications, understanding that material degradation has a significant impact on the lifespan and performance of products. Understanding a material's resistance to abrasion ensures that the chosen material can endure the wear it will encounter in its intended use.
• Effects of material degradation:
  • Reduced mechanical strength and structural integrity
  • Increased wear and tear
  • Impaired functionality
  • Safety hazards
  • Increased maintenance and replacement cost
  • Reduces life of product
  • Negative brand image and customer satisfaction

  To mitigate the impact of material degradation on product lifespan and performance, thorough understanding of material properties, regular inspections, proper maintenance practices, and the use of robust materials that resist degradation are essential.

  Implementing effective quality control measures, including abrasion and wear testing, is crucial to identify potential degradation issues early on and ensure the durability and reliability of products.

• Quality control: Manufacturers use abrasion resistance testing as part of their quality control processes to ensure that produced materials or products meet predefined standards. This helps prevent premature failures and costly recalls.
• Research and development:Researchers use abrasion resistance testing to study the effects of various factors on material wear. This information guides the development of new materials with improved durability.

Common Abrasion Resistance Test Methods:

A material's resistance to abrasion can be measured using a variety of standard tests, including ASTM, DIN, ISO and JIS methods. Below list includes some of the most common for the paint and coatings industry.

Types of Abrasion Testers

Abrasion resistance testing equipment is used to measure a material's resistance to abrasion. Abrasion testers provide a repeatable, controlled condition to simulate everyday use or wear patterns. The abrasion testers have a flexible design for coated and uncoated surfaces that need to be assessed for resistance to abrasion caused by a brush, sponge, scouring pad, sandpaper, and other means to abrade the surface.

This is carried out by subjecting the material to a set amount of wear over a specific period of time, or by measuring how much of the material is worn away through rubbing or friction. Abrasion testing equipment can be used to evaluate a variety of materials, including metals, plastics, and composites and is common for tile, flooring, furniture, wall coverings, shower stalls, and bathtubs.

There are several common types of abrasion testers used to assess the resistance of materials to abrasion and wear. These testers vary in terms of their testing principles, applications, and the types of materials for which they are suitable. Here are some of the most common types:

1. Taber abrasion testers: The Taber Abrasion Testers utilize a rotating platform with abrasive wheels or discs that are pressed against the material's surface. The material is subjected to both abrasive and compressive forces, simulating abrasive wear conditions. This tester is widely used for evaluating the abrasion resistance of coatings, textiles, plastics, and other flat materials.
2. Dry rubber wheel abrasion testers: This tester employs a rotating rubber wheel, which is applied against the surface of the test material. It is used to assess the wear resistance of materials like rubber, leather, textiles, and coatings. The tester can be adjusted to vary the load and speed, enabling the simulation of different wear conditions.
3. Dry rubber wheel abrasion testers: Sand-slurry abrasion testers involve the suspension of abrasive particles (such as sand) in a liquid medium. This mixture is then directed onto the material's surface using a nozzle or impingement apparatus. The material is evaluated based on the loss of mass or volume after a specified period. This method is often used to assess the wear resistance of metals, ceramics, and other materials under erosive wear conditions.
4. Falling sand abrasion testers: The procedure for this abrasion tester involves abrasive particles falling through a guide tube and impinging the test specimen, until the substrate becomes visible.
5. Pin-on-disk tester: In this type of tester, a stationary pin is pressed against a rotating disk. The contact between the pin and the disk generates friction and wear. This tester is particularly useful for evaluating the wear behavior of materials under dry sliding conditions. It allows for the study of fundamental wear mechanisms and the effects of various parameters such as load, speed, and lubrication.
6. Ball-on-plate tester: This tester involves a spherical ball that rolls under a load on a flat plate specimen. It is commonly used for assessing the wear resistance of materials under rolling and sliding wear conditions. The test can be adjusted to simulate different contact geometries and loading conditions.
7. Oscillating abrasion testers: This tester can measure the relative resistance of a material to the surface abrasion caused by an oscillating abrasive media. Ideal for rigid specimens that are 100mm square and less than 12.5mm in thickness. Specimen is mounted in a holder in the bottom of a sand tray filled with a standardized abrasive media such as quartz silica or alumina. A scotch-yoke drive system reciprocates the tray in a back-and-forth motion which causes the entire mass of the abrasive media to shift significantly within the tray. The abrasive media's oscillating movement results in a random pattern of scratches which simulates normal everyday wear.
8. Reciprocating abrasion testers: Counterbalanced arm which pivots on an adjustable height gantry system. Balancing of the test arm by a counterweight ensures precise test load set-up regardless of the weight of the attachment. Ideal for flat surfaces.
9. Shear/ Scratch abrasion scrub testers: Evaluate resistance to shearing, scratching, gouging, marring, scraping and engraving on flat, rigid specimens. The turntable which is motorized rotates at a constant speed to ensure accuracy in test results. The best results will be obtained by performing three to four tests on the specimen surface.
10. Rub testers: Are motor driven instruments for moving a weighted test strip over a printed specimen through an arc. Various rub testers can perform Dry Rub, Wet Rub, Wet Bleed or Transfer, Wet Smear, and Functional Rub tests. Ideal for testing inks.
11. Microscale and nanoscale abrasion testers: These testers focus on evaluating abrasion and wear at exceedingly small scales, often using advanced microscopy techniques. They are crucial for studying wear behavior at micro and nanoscales, which is particularly relevant for applications involving microelectromechanical systems (MEMS), nanocomposites, and coatings.
12. Abrasion scrub tester - scrub abrasion tester - washability machine - washability tester: This tester evaluates materials' resistance to wear and abrasion by using scrub media under wet conditions. It involves exposing the material to a combination of abrasive particles and a liquid medium, simulating conditions met in wet environments. The most common applications for testing scrub resistance are testing of floor tiles, shower stalls, painted interior walls and furniture surfaces. Abrasion Scrub Testers are also used to test the washability of coatings and other surfaces. Scrub Abrasion or Washability Testers examine the washability of a coated surface for the removal of stains, as well as testing and evaluating detergents and cleaning solutions in a reproducible manner. Scrub abrasion washability machines span the range from the simple to sophisticated supplying force recording of test motion resistance, which has the potential of eliminating subjective operator evaluations.
13. Reciprocating sliding wear tester - linear motion tester - wear tester: This tester involves back-and-forth linear motion between the test material and a counter material. It is used to simulate sliding wear conditions, often encountered in applications like bearings, seals, and gears. Linear motion test equipment with force measurement capabilities are ideally suited for measuring friction. Models with cut-out bases are designed for making measurements not only on prepared samples but also directly on the substrate surface such as tile, wood, laminate flooring. The variable rate features of these machines permit operating at a sufficiently low velocity so that kinetic energy and momentum factors may be neglected. A velocity of three to five inches per second is suggested when working with most surfaces.

These are just a few examples of the most common types of abrasion testers. The choice of tester depends on the specific material being evaluated, the intended application, and the wear conditions that need to be simulated.

Factors Affecting Abrasion Resistance Testing:

The outcome of abrasion resistance testing is influenced by various factors:

• Material Properties: Hardness, elasticity, toughness, and surface finish of the material significantly affect its resistance to abrasion.
• Abrasive Type: Different abrasives, such as sand, grit, or diamond particles, simulate different wear scenarios and affect test results differently.
• Load and Pressure: The applied load and pressure influence the severity of abrasion. Higher loads can lead to more significant wear.
• Testing Conditions: Factors like humidity, temperature, and the presence of lubricants can mimic real-world conditions and affect test outcomes.

Common Applications for Abrasion Resistance Testing:

• Automotive and Aerospace: Testing abrasion resistance helps evaluate the durability of vehicle components, such as tires, brake pads, and interior materials.
• Construction: Materials like tile, concrete, asphalt, and coatings are tested to ensure they withstand the abrasive effects of traffic and weather.
• Textiles: Fabrics undergo abrasion resistance testing to determine their suitability for clothing, upholstery, and other applications.
• Mining and Manufacturing: Equipment exposed to abrasive materials like rocks, minerals, and chemicals are tested to ensure prolonged operational life.

Conclusion

Abrasion resistance testing and wear testing offer valuable insights into the durability and performance of various materials. These tests help engineers and researchers understand how materials withstand friction, contact, and repetitive use, mirroring real-world scenarios. By subjecting materials to controlled abrasion and wear conditions, it becomes possible to evaluate their resistance to degradation, erosion, and surface damage over time. This information is vital for selecting materials for specific applications, designing long-lasting components, and improving product quality. With applications spanning diverse industries, a comprehensive understanding of abrasion resistance testing is essential for designing durable and long-lasting materials and products. Abrasion and wear testing also enable the development of effective protective coatings, lubricants, and surface treatments, which can enhance the lifespan and reliability of materials in demanding environments.