Concerning the Mechanisms of Fiber and Yarn Lubrication

Abstract

In the past, the main approach to the problems of friction and its modification, as they apply to textile structures, has been to determine the coefficient of friction and to develop a general determinant for this constant. It is suggested in this paper that a quantitative measure of the frictional relationships between fiber and fiber or between fiber and some other material, rather than being a reasonably constant quantity, is a highly unreasonable variable. This is especially true if the fiber is coated with a finish, which is usually the case; then in addition to depending on such variables as contact pressure and area, stress-strain characteristics of the fiber, etc., the coefficient of friction will depend on such factors as the physical and chemical Characteristics of the finish, the amount of finish present, the relative speeds of the surfaces in frictional contact, and so on.

The authors feel that it may be of greater practical significance to evaluate qualita tively the changes that take place in the frictional characteristics (type as well as magnitude) with given changes in the above-described variables. The observed behavior may then be related to performance in the various unit processes employed in textile manufacturing. Evidence justifying this point of view is presented in the paper, and some rather speculative explanations correlating finish properties and frictional behavior are given.