How to Conduct Taber Abrasion Test – ASTM D4060

What’s the Taber Abrasion Test?

Abrasion: in the relative motion of objects in contact with each other, the phenomenon of continuous loss, transfer or residual deformation of surface materials is called abrasion, which is the inevitable result of friction. Most abrasion not only consumes materials and wastes resources but also directly affects the life and reliability of objects.

The abrasion process is very complex, and there are many factors that affect the abrasion speed: different materials, different abrasion modes, and test environment. Taber abrasion test is a method to simulate the abrasion of materials in the laboratory, which is widely used in all kinds of materials, including plastics, coatings, laminates, leather, paper, textiles, floors and so on.

 In this paper, the test method ASTM D4060 is used to explain how to conduct the Taber abrasion test in four ways. 

1 Test scope

ASTM D4060 test method covers the determination of the resistance of organic coatings to abrasion produced by the Taber Abraser on coating applied to a plane, rigid surface, such as a metal panel.

2 Sample preparation

Take samples according to the specification of the available material or the agreement of the buyer and the seller. If there is no related description, then take the width of the whole fabric and the length at least 50cm, and should be sampled at 1m from the end of each piece of fabric.

The sample is a disk or square, and there is a hole with ø6.5mm in the center of the sample. The test sample is a circle with a diameter of 100mm or a square of 100mm*100mm. The thickness of the sample should not be more than 6.3mm, and the test thickness of the sample can be adjusted.

Unless otherwise agreed upon between purchaser and seller, condition the coated panel for at least 24h at 23±2℃ and 50±5% relative humidity. Conduct the test in the same environment or immediately on removal therefrom.

3 Test procedure

3.1 If either the wear index or the weight loss is to report, weigh the test sample to the nearest 0.1mg and record this weight.
3.2 When the abrasion coefficient needs to be calculated in mil, measure the coating thickness of the test specimen in several locations along the path to be abraded, and averaged.
3.3 Mount the test specimen on the turntable platform of the Taber abrasion tester, and the side to be ground faces up, fixed with splint and nut. Lower the two grinding wheels with a certain load, just touching the surface of the sample. Set the number of rotations, open the vacuum cleaner, and start the test.
3.4 Subject the test specimen to abrasion for the specified number of cycles or until wear through of the coating is observed. In determining the point of wear through, stop the instrument at intervals for an examination of the test specimen.
3.5 Remove any loose abrading remaining on the test specimen by light brushing and reweigh the sample.

The operation of Taber abraser as follows:

4 Calculation

4.1 Abrasion index: 1000 times the loss in weigh in milligrams per cycle, the unit is mg.

I = 1000 (A – B) / C

Where:
A = weight of test sample before abrasion, mg
B = weight of test sample after abrasion, mg
C = number of cycles of abrasion recorded

4.2 weight loss: the loss in weight in milligrams, determined at a specified number of cycles.

L = A – B

Where:
A = weight of test sample before abrasion, mg
B = weight of test sample after abrasion, mg

4.3 wear cycles per mil: the number of cycles of abrasion required to wear a film through to the substrate per mil of film thickness.

W = D / T

Where:
D = number of cycles of abrasion required to wear coating through to substrate
T = thickness of coating, mils (0.001 in.) (to one decimal place).

Note: In calculating the wear cycles, it is advisable to discard the first and last readings because the first may be affected by an uneven surface and the last by abrasion of parts of the substrate.

The Taber abrasion test is very effective and is the most common test method when evaluating the abrasion resistance of the coating on the matrix. It can not only conform to the ASTM D4060 standard, but also conforms to the ASTM D3884, ASTM D3389, and ISO 5470, etc. If you want to know more, take a look at Taber abrasion tester (Taber abraser).