Comparison and selection of Martindale flat grinding method and TABER wear method
23 \ May
The abrasion resistance of leather is the property that leather has to resist wear and tear. The wear of leather is an important reason for the damage of leather. Although the wear fastness of leather has not yet been assessed as a national standard, but the abrasion resistance experiment of leather is still indispensable to measure its quality, and it is extremely important to assess the taking fastness of leather.
According to the test with different instruments, there are two methods commonly used: Martindale flat grinding method and TABER wear method
1, martindale flat grinding method (10000 times) - martindale wear-resistant instrument
(1)Reference standard: "GB/T21196-2007 Martindale method for the determination of fabric abrasion resistance".
(2)Test apparatus: There are many types of fabric flat abrasion apparatus, at present the test industry uses a lot of Martindale apparatus, so the flat abrasion method is also often called MARTINDALE friction testing machine method.
(3) test principle: the circular specimen installed in the Martindale abrasion tester specimen jig, under the specified load, to Lissajous (Lissajous) graphic plane movement and abrasive (i.e., the standard fabric) for friction, the specimen jig can be freely rotated around its axis perpendicular to the horizontal plane. According to the total number of friction of the specimen broken, to determine the abrasion resistance of leather.
(4) Test method: The test will be a certain size of the test sample under the specified pressure and standard abrasive contact with each other, and make the test sample to Lishajou trajectory relative to the abrasive movement, so that the test sample is subject to multi-directional uniform wear.
2、TABER abrasion resistance method (1000 times) --Taber abrasion resistance test machine
(1)Reference standard: "GB/T2726-2005 Determination of abrasion resistance of leather physical and mechanical test".
(2)Test apparatus:
TABER abrasion resistance tester
(3)Test principle: Pre-grinding 25 revolutions, the specimen to be tested is placed on the horizontal platform of TABER abrasion resistance tester and rotated, two grinding wheels are given specific pressure to press on the test piece optionally, the axes of the grinding wheels are parallel to the horizontal plane, one grinding wheel facing outward and the other facing inward, and all changes of the test piece are recorded within a certain period of time.
(4) Test method: Cut the sample with a cutter of 108mm outer diameter and 8mm inner diameter. Then put a hard sticker of the same size on the back of the sample. Place the sample center hole on the rubber pad of the screw, put the pad on, and fix the sample with the compression nut. Then put the fixing ring on, and lock the fixing ring screw with a wrench. Attach two H18 grinding wheels to the support arm, and apply a force of 250±10g per wheel to the sample under test, ensuring that the side with the label faces outward, so that the negative weight of the grinding wheels is 500g. Connect the vacuum cleaner, connect the vacuum cleaner's dust pipe to the connector on the left side of the machine, and start the vacuum cleaner. Set the number of tests according to the standard regulations and set the slewing speed to 72 rpm. Then start the start button, turn on the instrument with a rotation speed of 60±5 times/min, rotate horizontally and test according to the required number of times. During the test, use the brush to brush away the surface attachment of the specimen, observe the wear and tear of the test, grind the leather to the specified end point, and record the final number of revolutions.
From the above two test methods, the results of the abrasion resistance test methods for different materials are expressed differently. the MARTINDALE friction tester method expresses the abrasion resistance by the end point and the change in appearance. the TABER abrasion tester method records the number of times of friction as an index of abrasion resistance.
It is not meaningful to compare test results obtained by testing different materials and using the same experimental method, but these results lead to the same conclusion. Therefore, either method can be used independently to quantitatively evaluate the abrasion resistance of a material. Comparing the above test results shows that, in general, natural leather is a softer material and therefore has poorer abrasion resistance. Coated leather is harder and less susceptible to abrasion, and therefore has better wear resistance.
For leather products, wear resistance is also related to the size, shape, testing environment, taking environment, subjective error, instrumentation, etc. Therefore, when we judge the wear resistance of leather, we need to consider all factors as much as possible to get a more objective answer.