Comparison between aluminum alloys 7075 machined by tool with polished carbide insert and carbide insert coated with TiB2

Cleverson Pinheiro¹; Vitor Carlos Silva Nicolau²; Manoel Cléber de Sampaio Alves²; Marcos Valério Ribeiro²

¹ UNESP - FEG Guaratinguetá. IFSP, Campus Jacareí; ² UNESP-FEG

doi:10.20906/CPS/COB-2015-1066

Resumo

The physical, chemical and mechanical characteristics of the materials used in cutting tools, as well as the geometries of these result in different behaviors and results in machining of materials. The behavior of each tool can vary also depending on the material to be machined and the machining process variables. Different technologies are being applied to improve the characteristics of the cutting tools such as application these materials coating tools with specific chemical and physical characteristics, coupled with a greater or lesser degree of surface finishing of these tools. The present study aimed to analyze the influence of different materials of cutting tools in the process of turning aluminum alloy 7075 used mainly in the field of metalworking, automotive, aeronautical and marine, as well as check and compare the influence of feed rate and depth of cut on the surface finish and power required during the process. We compared the tools with carbide insert coated with titanium diboride (TiB2) and polished carbide insert in three forward speeds and three depths of cut in machining operation by external cylindrical turning with the aluminum alloy 7075. We collected data instantly power consumed during rehearsals of machining, as well as collections of average roughness values (Ra) and total (Rt) of specimens. For the study of the variables was used a completely randomized complete factorial planning. Statistically significant differences were observed, at a significance level of 5%, between the two cutting tools and the three forward speed to the surface finish. For the power consumed, also considering a significance level of 5%, significant differences were observed between levels of all factors examined, in addition to a degree of correlation between the power consumed and analyzed variables.

Palavras-chave: Surface quality; Material machining; Methods of measuring; Improvement of materials