The Compaction and Consolidation of Machining Chips: Experiments and Modeling
The Friction Extrusion Process (FEP) provides a novel method to recycle machining chips to produce useful products such as wires. It is a solid-state process since there is no melting involved. The first stage of this process is the compaction and consolidation of the chips inside the process chamber, which serves as the basis for the subsequent stage of friction extrusion in which the consolidated chips are softened due to frictional heating and are turned into wires through an extrusion hole in the die. The compaction and consolidation process is an essential step in FEP since it helps to determine the property and quality of the final product. The current study focuses on gaining an understanding of the compaction and consolidation process through experimental investigation and numerical modeling. In order to understand the characteristics and material behavior of the chip material during the compaction and consolidation process, discontinuous machining chips of aluminum alloy 6061 with several chip lengths were used in the study. A non-rotating solid die without a central extrusion hole was used to compress the chips and produce a consolidated disc. The chips as a whole were considered as a porous continuous material with a certain starting density that will change during compaction and consolidation. The dependence of elastic and elastic-plastic properties of the porous material on the changing density was investigated and a mathematical model for the elastic-plastic behavior was developed.
Authors: N. Abbas, X. Deng, X. Li, and A.P. Reynolds
Conference: SAMPE Seattle 2017