Finite element modeling of erosive wear M.S. ElTobgy * , E. Ng, M.A. Elbestawi McMaster Manufacturing Research Institute, McMaster University JHE 316, 1280 Main St. W, Hamilton, ON, Canada L8S 4L7 Received 3 June 2004; accepted 13 January 2005 Available online 3 March 2005 Abstract Material damage caused by the attack of particles entrained in a fluid system impacting a surface at high speed is called ‘Erosion’. Erosion is a phenomenon that takes place in several engineering applications. It also can be used in several manufacturing process such as abrasive waterjet machining. Erosion is a complex process dependent on particle speed, size, angle of attack as well as the behavior of the eroded material. Extensive experimental results have been reported in the literature on the erosion of different materials. Simulating the erosion process through finite element enables the prediction of erosion behavior of materials under different conditions, which will substitute the need of experimentation, and will enable the identification of constants required for existing analytical models. In this paper, an elasto-plastic finite element (FE) model is presented to simulate the erosion process in 3D configuration. The FE model takes into account numerical and material damping, thermal elastic–plastic material behavior and the effect of multiple particle impacts as well as material removal. The workpiece material modeled was Ti–6Al–4V. The effects of strain hardening, strain rate and temperature were considered in the non-linear material model. Comparison against results reported in literature and erosion models by Finnie, Bitter and Hashish are made. It is shown that the predicted results are in agreement with published results obtained experimentally and from analytical erosion models. q 2005 Elsevier Ltd. All rights reserved. Keywords: Erosion; Finite element modeling; Elastic–plastic 1. Introduction The erosion of materials caused by impact of hard particles is one of several forms of material degradation generally classified as wear. Bitter [1] defined erosion as “Material damage caused by the attack of particles entrained in a fluid system impacting the surface at high speed” while Hutchings [2] wrote “Erosion is an abrasive wear process in which the repeated impact of small particles entrained in a moving fluid against a surface results in the removal of material from that surface”. Solid particle erosion is a serious problem in gas turbines, rocket nozzles, cyclone separators, valves, pumps and boiler tubes. However, solid particle erosion can be utilized in manufacturing processes such as abrasive waterjet cutting. Removal of material occurs through the processes of micro-plastic deformation and/or brittle fracture. For ductile materials such as pure metals and alloys, the impact of the hard particles causes severe, localized plastic strain at the impact site on the surface. Material is removed when the strain exceeds the material’s strain-to-failure. For brittle materials, such as ceramic and intermetallic compounds, the force of the impacting particle causes localized cracking at the surface. With subsequent impact events, these cracks propagate and eventually link together, and as a result, material becomes detached from the surface [3]. As a consequence, the particle impingement angle on the surface affects each material in a different manner. Material loss for ductile metals tends to peak at an oblique angle of impact, typically between 20 and 308. However, material loss for brittle materials tends to increase with increasing impingement angle with maximum material loss occurring at 908 [4]. Alman’s [3] studies on both ceramics and metals suggest that the attack angle is the best indicator for the erosion mechanism. Ductile materials exhibit maximum erosion rates at attack angles of about 20–408 while brittle materials exhibit a maximum erosion rate at an angle of 908. No external forces act on the impacting particle other than the contact forces exerted by the work piece material International Journal of Machine Tools & Manufacture 45 (2005) 1337–1346 www.elsevier.com/locate/ijmactool 0890-6955/$ - see front matter q 2005 Elsevier Ltd. All rights reserved. doi:10.1016/j.ijmachtools.2005.01.007 * Corresponding author. Tel.: C1 905 525 9140x24058; fax: C1 905 572 7944. E-mail address: eltobgm@mcmaster.ca (M.S. ElTobgy).