Effects of ball burnishing on surface properties of low density polyethylene

We have end milled surfaces and then applied ball burnishing to specimens of low density high molecular mass polyethylene (LDPE). An important objective was roughness minimization. For selected ball diameters, the influence of burnishing parameters such as force F and burnishing speed f on selected surface geometry parameters has been determined: roughness Ra, total height of the profile Rt, and also the two-dimensional roughness change K-Ra. We find the minimum value of Ra=0.57 mu m and the maximum value of K-Ra=5.1, both highly desired results. In the best case, Rt has decreased from 14.5 mu m to 4.0 mu m. Microhardness values, ball-on-disc wear values and scratch resistance testing all show property improvement of milled and burnished surfaces as compared to surfaces milled only. Burnishing decreases the wear rate by 58%. (C) 2015 Elsevier Ltd. All rights reserved.