Movements,Lissajous,rubs and cycles of Martindale and Wyzenbeek

The Wyzenbeek Abrasion Testeris a type of abrasion testing instrument. The Wyzenbeek instrument first came into use around the early 1920s in the United States. It uses an oscillating cylinder covered with abradant to rub against the specimen being tested, which is held stationary against the abradant under pressureand tension.

The Martindale Abrasion Tester was developed by J.G. Martindale in the early 1940s under the auspices of the Wool Industries Research Association in England. It uses an oscillating top plate to move a circular test specimen in a grouping of elliptical repeating paths over a stationary abradant under pressure. There are a set of 16 sequentially changing ovals or back and forth ellipses executed in each repeating group. The precise repeating group is known as a Lissajous figure.

Quantifying The Abrasion Resistance Of Textiles can be performed in several ways each of which requires the rubbing of the fabric of interest against a standard abradant and the assessment of how much abrasion it takes to either create a hole, aesthetic deterioration, strength loss or mass loss.

Upholstery testing product performance specifications use the amount of abrasion required to create a two yarn break hole in the fabric of interest as the quantitative operational definition of abrasion resistance. The amount of abrasion is measured by the counter on the abrasion testing instrument.

For the Wyzenbeek, each time the cylinder moves forward and backward the counter on the front of the instrument is incremented by 1. This cyclical movement is typically referred to as a cycle or double rub and is defined this way in the current ASTM D4157 Test Method. The video below shows the Wyzenbeek in action with the abrasion count as it would be used in a Contract Upholstery or similar product performance specification:

Traditionally on the Martindale instrument every time an elliptical back and forth path is completed the counter on the front of the instrument is incremented by 1. This single elliptical or oval back and forth path is commonly referred to as a rub in Europe or in common parlance as a cycle in the United States. It is currently defined in ASTM D4966 as a movement but the term movement is almost never used in reporting Martindale abrasion test results or in product performance specifications referencing Martindale abrasion.

ISO 12947-1:1998(E) refers to ASTM movements as rubs. Abrasion cycles are technically defined in both ISO 12947 and ASTM D4966 as the 16 movements or rubs making up the Lissajous repeat however it should be kept in mind that the use of cycle in this manner is not commonly used in industry. U.S. product performance specifications and test reports use the word cycles as being synonymous with ASTM movements or ISO rubs.

The video below shows the Martindale in action performing ASTM D4966 with the abrasion count in cycles as it would be used in a U.S. contract upholstery or similar product performance specifications shown in blue on the top row of text. Rubs, ISO Cycles, ASTM Abrasion Cycles, and Lissajous Cycles are also shown.

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