Effect of cutting parameters and machining environments on the chips characteristics and surface quality of commercial high-conductive materials

The present paper is on the physical and mechanical characterization of machined chips of commercially available highly conductive metallic materials, namely aluminium and copper under different machining environments. More specifically, geometry and hardness of chips as well as the chips removal effect on the machined surfaces are investigated in a quantitative fashion as a function of machining fluid and cutting parameter. The machining is carried out by using a horizontal shaper machine with a V-shaped HSS tool under three different machining fluids, where the feed rate is kept constant, while the cutting speed and depth of cut are varied. The geometry and hardness of the machined chips as well as the quality of machined surfaces are found to be affected quite significantly by the change of machining condition, particularly by the machining fluids.

Effect of Slide Burnishing on the Surface Layer and Fatigue Life of Titanium Alloy Parts

The paper presents the results of a study investigating the effect of slide burnishing on the surface roughness, surface layer microhardness and fatigue life of Ti6Al2Mo2Cr titanium alloy parts. The burnishing process was performed with the use of a diamond tip tool. Different machining fluids were used as machining media. Prior to burnishing, the samples were subjected to turning. The burnishing process led to reduced surface roughness (average roughness Ra decreased by 3.5 times and roughness Rz decreased by 2.5 times) as well as increased surface layer microhardness (microhardness maximum increase by 12%) and fatigue life of the tested parts. A relationship between the machining medium and the burnishing effects was also observed. The addition of a surface-active polymethyl methacrylate solution to the machining medium led to an increase in the surface layer microhardness and fatigue life of the workpiece.

Evaluation Method for Friction Coefficient of Machining Fluids Using Cutting Force in Micro Feed End Milling

In conventional friction tests, it is difficult to realize the high pressure and high temperature conditions of the tool-work contact area in cutting. In this study, the friction properties of machining fluids were evaluated using a friction coefficient calculated from the cutting force in micro feed end milling. The finished surface roughness in conventional end milling decreased with the friction coefficient of machining fluids obtained by this method. Also, the cutting speed dependence of the friction coefficient, and its influence on the biting property of the cutting edge can be evaluated by this method.