1 Investigation of the effect of different cutting parameters on chip formation of low lead brass with experiments and simu- lations PUBLISHED IN: Laakso SVA, Hokka M, Niemi E, et al. ”Investigation of the effect of different cutting parame- ters on chip formation of low-lead brass with experiments and simulations.” Proc IMechE, Part B: J Engineer- ing Manufacture 2013; 227(11): 1620–1634. Sampsa V.A. Laakso # , M ikko Hokka + , Professor Esko Niemi # , Professor Veli-Tapani Kuokkala + # Aalto University School of Engineering, Department of Engineering Design and Production + Tampere University of Technology, Department of M aterials Science Corresponding author details: M r. (MS(tech.)) Sampsa Vili Antero Laakso E-mail: sampsa.laakso@aalto.fi Phone: +358 504060 588 Address: Puumiehenkuja 3, 02150 Espoo, Finland http://users.aalto.fi/~svalaaks/ KEYWORDS: Cutting, Material Modeling, Finite Element Method, Low Lead Brass, Chip Breakage Abst ract Poor chip breakage causes problems in machining of low lead brass. To improve chip breakage, finite ele- ment-simulations (FEM) were implemented in cutting tool design. FEM-simulations enable high number of experiments that would be expensive and slow to perform by conventional cutting tests. Compression tests and cutting experiments under different temperatures and strain rates were performed for lead free brass, to acquire material parameters for the FEM model. It was observed that the coupled effect of thermal sof- tening and rate sensitivity of the material was difficult to take into account with the existing material mod- el. Furthermore, it was found out that there are no reported material models that can take rate sensitivity- temperature coupling into account. This was counteracted by fitting the model with least square method to the stress strain data at the cutting temperature, although this causes error in simulations with tempera- tures higher or lower than the supposed cutting temperature. Nevertheless, the simulated results proved accurate enough to model the chip breakage. Based on the simulations and experiments, the use of a posi- tive rake angle, high cutting speed and low cutting feed rate improve chip breakage from continuous chip to a chips of average length of 4 mm. Introduction Health and environmental issues are growing concerns for companies and governmental decisions. In the United States, the state of California has banned plumbing products containing lead more than 0.25 % (1). The restriction took effect on 1 st of January 2010 despite the opposition of The Plumbing Manufacturers Institute (2). Exposure to lead is a commonly known major health hazard, as it can cause anaemia and pro- voke other health issues (3). The restriction affects especially brass components, which are typically ma- chined from cast billets. Typical cast brass alloys with good machinability contain lead between 1.5 and 3 %. (4) Some companies have decided to substitute lead with bismuth, though there are references according to which bismuth could also be toxic (5),(6). Finnish faucet & plumbing industry has decided to use lead free