Accession Number : AD0690618

Title :   EFFECT OF OXIDE FILM ON THE FRICTION OF 52100 STEEL IN VACUUM.

Descriptive Note : Rept. for Jan 67-Sep 68,

Corporate Author : DAYTON UNIV OHIO

Personal Author(s) : Takagi,Riitsu

Report Date : APR 1969

Pagination or Media Count : 38

Abstract : To solve the problem of sudden drop of friction coefficient in reciprocated slidings of 52100 bearing steel in ultrahigh vacuum, friction studies were made of a 52100 test steel ball sliding on a 52100 steel flat reciprocally with a 9.5 mm long stroke at an average speed of 2 mm/sec under 500 to 1000 g loads in vacuum. In ultrahigh vacuum sliding, the friction coefficients starts from 0.2 - 0.5, increases to a maximum 1.0 - 1.2 and drops to 0.5 - 0.6 at 20-100 traverses. After the drop no basic change of friction coefficients takes place other than a very gradual increase. Both friction force-time curves and the sliding areas change from smooth to rough when the friction undergoes the drop. The maxima and following drop of the friction coefficient vs. number of traverses plots are ascribed to build-up and rupture of oxide film that forms on the surface of the 52100 steel specimen in atmosphere. The friction is affected by applied load, finish mark direction on the relative to sliding and air pressure in the test chamber. (Author)

Descriptors :   (*STEEL, *FRICTION), VACUUM, BALL BEARINGS, METAL PLATES, CLEANING, THEORY, VACUUM APPARATUS, STRAIN GAGES, SURFACE ROUGHNESS, MICROSCOPY, OXIDES, LUBRICANTS, SLIDING CONTACTS

Subject Categories : Metallurgy and Metallography
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE