Influence of Internal Roller Burnishing Process Parameters on Surface Characteristics For Aluminum Alloy- 2024 ,T361

Abstract

Several techniques can be used to improve surface properties of metals . These can involve changes on the surface chemical composition such as alloying or on the surface microstructure such as hardening or on the burnishing such as improved surface finish ,increased microhardness ,corrosion resistance and fatigue life as result of the produced compressive residual stress . In the present work surface was improved (surface roughness) and increased surface microhardness with a roller burnishing of aluminum alloys 2024,T361 . Surface roughness characterization was done by an Surtonic3+Instrument ,mechanical features surface microhardness before, and after internal roller burnishing were evaluated by Vickers microhardness test ,and microstructure characterization was tested by an optical microscope ,grain size transformations (change microstructure) rapid solidification was then analyzed and discussed . This research was aimed to determine the optimal setting of the process parameters on the internal roller burnishing and effect of working parameters on average roughness , surface microhardness and microstructure ,the aluminum alloys 2024,T361 was used as a workpiece . 50 diameter model DT5000 adjustment range (-0.2/+0.6mm) produced in north India by (DYNEMECH SYSTEMS PVT.LTD) was used as the internal roller burnishing tool. The experiments were done on an CNC milling machine model Bridgeport VMC500 by using Taguchi methodology .The Taguchi method is used to formulate the experimental layout and analyze the effect of each parameter on the burnishing characteristics, and to predict the optimal choice for each burnishing parameter such as burnishing speed, burnishing feed and tool diameter. Analysis of variance (ANOVA) used F-test to investigate which process parameters significantly affect the performance characteristics ,and the percent contribution of these parameters on surface roughness , surface microhardness and microstructure . In general it is found that the tool diameter mainly affect the surface roughness ,while the tool diameter and burnishing speed significantly affects the surface microhardness from the microstructure there is notesable change in the surface integrity reported.