Determination of the Brinell number of metals

Serge N. Petrenko, Walter Ramberg, Bruce Wilson
1936 Journal of research of the National Bureau of Standards  
The procedure used in making Brinell t ests must be closely controlled in order that t wo observers testing a given metal at different locations should obtain Brinell numbers that are in close accord. Small variations in testing procedure will be inevitable so that it becomes important to know the effect of these variations on the magnitude of the Brinell number obtained. The present paper considers the effect on the Brinell number of such variations with the help of data available in the
more » ... ilable in the literature supplemented by new t est s wherever the existing data seemed deficient. Attention is given to the effect on the Brinell number of variations in t esting procedure, i. e., rate of applying loa d, time under nominal load, error in load, and error in measuring the diameter of indentation. The effect of variables residing in the specimen is discussed n ext under the separate heads of nonuniform properties, curvature of surface, thickness, spacing of indentations, and angle between load line and normal to specimen. Variations in the t ype of ball used were considered last, particular attention being pa id to differences in elastic deformation and in p ermanent compression of the ball u nd er load. The paper concludes with recommendations for· a t est procedure which would lead to greater concordance in the Brinell numbers obtained by different observers using a ball of given diamet er on a sp ecimen of given metal. Journal of Research of the National Bureau of Standards Resea rch Paper 903 FIG URE I.-Machine for making B rinell te8t and micrOSC01Je for measuring diameter oj indentation. Petrenko, Ramberu,] Wilson
doi:10.6028/jres.017.029 fatcat:32u5tlfhirbbplaqbmvlubdcuy