Tensile testing machines, also called universal material testing machines, are testing machines that test the…
The abrasion resistance of textiles refers to the wear resistance between fabrics or between fabrics and other substances during repeated friction. There are various methods for testing the abrasion resistance of textiles, such as the flat abrasion method, the curved abrasion method, the folded edge abrasion method and the compound abrasion method. The Martindale method is one of the flat abrasion methods and is widely used for testing the abrasion resistance of clothing and household textiles, decorative fabrics and furniture.
Table of Contents
★ 5 forms of fabric wear damage
In actual use, due to the different conditions of wear (e.g. force, size, abrasives, etc.), the structure of yarns and fabrics and the nature of the fibers are different, thus the mechanism of wear damage is different, with the following forms of damage.
1 During friction the fibres constantly collide with each other and fibre fragments break due to fatigue damage, resulting in the breakage of the yarn.
2 The fibers are pulled out of the fabric, causing a loosening of the yarn/fabric structure. After repeated action the fibres may be pulled out, leading to thinning of the yarn and fabric, and even disintegration.
3 Fibers are cut and broken, leading to breakage of the yarn.
4 The fibre surface is worn and fragments are lost from the fibre surface.
5 Friction generates high temperatures, causing melt or plastic deformation of the fibers. Affects the structural and mechanical properties of the fibers.
★ Three aspects of the Martindale method for testing the abrasion resistance of fabrics
The Martindale method is applied to the abrasion resistance of knitted fabrics, woolen fabrics, artificial leather, synthetic leather, etc. under a certain pressure. It is applied in the form of flat abrasion and is generally analysed and evaluated in three aspects: determination of the specimen breakdown, determination of the loss of mass and assessment of the appearance change.
|Determination of specimen breakdown||Under a certain load, the specimen is rubbed against the abrasive in the plane of the Lissajous curve, and the total number of rubs is counted to determine the abrasion resistance of the fabric when the specimen breaks.|
|Determination of mass loss||Under a certain load, the specimen in the fixture is rubbed against the abrasive in a Lissajous curved plane, when the specimen has been rubbed a specific number of times, the abrasion resistance is determined by the mass difference before and after rubbing.|
|Assessment of appearance change||A circular specimen is subjected to a defined load and rubbed against an abrasive medium (standard fabric) in a translational movement tracing a Lissajous figure. The evaluation of the abrasion resistance of the textile fabric is determined from assessment of the appearance change.|
The conditions for specimen breakdown are:
|woven fabric||Complete breakage of at least two separate yarns.|
|knitted fabric||Breakage of one yarn, resulting in a hole in the appearance.|
|pile or cut pile fabrics||Abrasion of the pile on the surface, with an exposed bottom or with tufts of pile falling out.|
|non-woven fabrics||Holes caused by friction, diameter ≥ 0.5mm.|
|coated fabrics||Coated partly damaged, exposed base fabric or with flakes of coating off.|
★ The standard system for testing the abrasion resistance of fabrics by the Martindale method
|ISO 12947.2||Textiles / Determination of abrasion resistance of fabrics by Martindale method, part 2: Determination of sample breakdown|
|ISO 12947.3||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 3: Determination of mass loss|
|ISO 12947.4||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 4: Assessment of the appearance change|
ASTM D4966: Standard Test Method for Abrasion Resistance of Textile Fabrics (Martindale Abrasion Tester Method)
|EN ISO 12947.2||Textiles / Determination of abrasion resistance of fabrics by Martindale method, part 2: Determination of sample breakdown|
|EN ISO 12947.3||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 3: Determination of mass loss|
|EN ISO 12947.4||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 4: Assessment of the appearance change|
|DIN EN ISO 12947-2||Textiles / Determination of abrasion resistance of fabrics by Martindale method, part 2: Determination of sample breakdown|
|DIN EN ISO 12947-3||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 3: Determination of mass loss|
|DIN EN ISO 12947-4||Textiles / Determination of abrasion resistance of fabrics by Martindale method, par 4: Assessment of the appearance change|
|BS EN ISO 12947.2|
|BS EN ISO 12947.3|
|BS EN ISO 12947.4|
Links and differences between different standard systems
The standards given above are highly influential at international level. Of these, the EU standard, the DN standard and the BS standard are all equivalent to the ISO standard. The Chinese standard is basically the same as the ISO standard, except that the application scope of the standard has been increased by the addition of coated fabrics and for the testing of coated fabrics, corresponding provisions for the breakdown of coated fabrics, friction load parameters, standard abrasives and replace requirements of standard abrasives have been added.
ASTM D4966 consists of two parts: the test method for abrasion resistance and the Martindale abrasion tester and auxiliary materials, in which the test methods are basically identical to ISO 12947.2, ISO 12947.3 and ISO 12947.4. The determination of mass loss and the assessment of appearance change differ slightly from ISO 12947.3 and ISO 12947.4 and there are simplified in terms of the end-point conditions of the test and the presentation of the test results.
★ The test procedure for textile abrasion resistance: Martindale method
Determination of specimen breakdown
This method is applicable to all textile fabrics, but not to fabrics with a low abrasion wear life.
1 Selection of abrasives. Different standard abrasives are selected according to the characteristics of the specimen.
Uncoated fabrics: woven plain wool fabrics.
Coated fabrics: No. 600 waterproof abrasive paper.
The abrasive is separated from the abrasive table by a wool felt. After the test, check the felt surface and replace it if it appears stained or worn.
2 Sampling method. At least 3 pieces, the woven fabric should contain different warp and weft yarns. For jacquard or fancy tissues, each characteristic part of a complete tissue should be included, and when a complete tissue or pattern is large, each part may be sampled separately.
3 Selection of fixture liner. Determine the mass per unit area of the specimen and record it as A. If A≥500g/m2, no foam liner is required, if A<500g/m2, a foam liner is added to the specimen fixture and replaced after each test.
4 Total effective mass of the friction load, which includes mounting bracket and loading weight. According to the technical specifications provided by the TESTEX TF 210, Martindale Abrasion and Pilling Tester, the weight of the mounting bracket: (2500±500) g and the loading weight: (395±7)g, (595±7)g.
Select three corresponding total effective masses for the friction load according to the specimen use and fabric characteristics
4.1 (795±7)g: for fabrics intended for workwear, upholstery, bed linen, technical fabrics.
4.2 (595±7)g: for fabrics intended for apparel and household textiles, excluding upholstery and bed linen, non-taking coated fabrics.
4.3 (198±2)g: for coated fabrics for garments.
5 Abrasive change interval
Standard wool fabric: 50,000 cycles; standard waterproof abrasive paper: 6,000 cycles.
6 Interval between inspections
Estimate the number of times the specimen is rubbed when it reaches breakdown, on this basis, set a certain number of rubs as an inspection interval to observe the wear state of the specimen surface.
7 Measurement results are expressed
Determination of the total number of rubs per specimen when it occurs breakdown as the abrasion count.
Determination of mass loss
Applicable to all textile fabrics, but not to fabrics with a low abrasion wear life. The requirements for the selection of abrasives, the sampling method, the specimen fixture liner, the total effective mass of the friction load and the abrasive replacement interval are the same as those used for the determination of specimen breakdown. These are not repeated here.
The interval between inspections and test data
Set a certain number of rubs as an inspection interval to observe the wear state of the specimen surface. The test ends when the sample is broken or when the specified number of rubs is reached.
The mass loss is determined in two cases: The first case, at each inspection interval, the difference between the mass of the specimen before the test and after the test, which is measured as Δmi. In the second case, the specimen reaches the wear point and the difference between the mass of the specimen before the test and after the wear test, which is measured as Δm.
Assessment of appearance change
This method is applicable to textile fabrics with a low abrasion wear life. The selection of abrasives, the sampling method and the selection of the specimen fixture liner are consistent with the method for determining the breakdown of textile specimens and are not repeated here.
1 Total effective mass of load: (198±2)g
2 Abrasive replacement interval: new foam and standard abrasives for each test.
3 Evaluation of changes in specimen appearance
The abrasion resistance test achieves the agreed surface changes and the rub count is used as a measure of abrasion resistance. Design appropriate inspection intervals to observe changes in the appearance of the specimen, including discoloring, fuzzing, and pilling. The test protocol should specify the level of discoloring, fuzzing, and pilling on the surface of the specimen, and the test result is expressed in terms of the number of times the specimen rubs when it reaches a certain level of discoloring, fuzzing, and pilling.
If the end point of the abrasion test is the rub count specified in the agreement, the post-test specimen is compared with the pre-test specimen and the degree of discoloring, fuzzing, and pilling is rated as a change in appearance quality.
Of the three methods of testing the abrasion resistance of fabrics by the Martindale method, the commonly used method is the specimen breakdown determination, which has a small error, intuitive and clear test results and easy comparison of the abrasion resistance of different fabrics, and is commonly used in garments and decorative fabrics. The mass loss determination method and the appearance change method have more complex test results, but they can reflect the abrasion resistance of specimens at different friction stages and have a strong practical use in manufacturing companies or research institutes for analysing the usage of fabrics. This article provides an overview of fabric abrasion resistance testing based on the Martindale method, in the hope that it will help textile quality inspectors to properly understand and apply the Martindale method for abrasion resistance testing.