In a hard roller burnishing operation, a hydrostatically borne ceramic
ball rolls over the component surface under high pressures. The rough
ness peaks are flattened and the quality of the workpiece surface is i
mproved. When combined with hard turning, this process provides a manu
facturing alternative to grinding and honing operations. The studies d
etermined optimum working parameter ranges. Parameter settings were sh
own to be noncritical in this process, since constant surface qualitie
s were attainable over wide setting ranges. A second phase of the stud
ies examined the improvements obtained for various original roughnesse
s. Reductions of 30 to 50 % in mean peak-to-valley height R-z are, for
example, achievable, depending on the original roughness. Structure a
nalyses and residual stress measurements were used to examine the effe
cts of the process on the workpiece surface zone. Hard roller burnishi
ng transforms tensile residual stresses present in the surface zone af
ter hard turning into compressive residual stresses. Hard roller burni
shing has no effect on the formation of white layers in the surface zo
ne. (C) 1998 Elsevier Science Ltd.