Experimental and Fe Analysis of Aluminium Alloy Plastic Flow in the Forward Microextrusion Processes

Abstract

Abstract The main aim of the paper is an evaluation of the real impact of a container surface roughness on metal plastic flow in the forward microextrusion process. For the purposes of experiment a specially designed and constructed by authors toolkit was used. Analyzed material was an annealed aluminium wire with 1,7 mm in diameter, with a stress-strain curve defined. Toolkit contains two experimental models of containers and rectangular dies with the same dimensions, differing only in the containers roughness degree. In order to determine the degree of the containers top layers asperities a roughness profiles with using laser microscope were made for each. Punch pressures have been calculated while forward extruding. In the next step the deflection of parallel lines marked at the samples longitudinal sections were analyzed. The extruded samples were submitted to the microhardness testing. Numerical analyses of analogous microextrusion processes have been also conducted. Container surface roughness was modelled as a rigid triangular wave with a zero friction factor at the interface m =0. Punch pressures and shapes of extruded samples flow nets were determined. Conducted investigations revealed the possibility of receiving products with different mechanical properties obtained by the container roughness assorting.