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The simulation of manufacturing processes has a large appeal for improving the performance of the Computed Aided Engineering in several industries using extensively casting, welding, forging and deep drawing. The numerical simulation of deep drawing processes became just recently a tool, as a consequence of the development new user friendly 3D Finite Element Explicit Time Integration Techinique codes for the improved workstations and supercomputers. Although the 3D Finite Element Implicit Time Integration Techinique are the best methods to analyse the quasi-static formulation, the computer time and memory size required are too large. This paper is focused on the application of the numerical simulation with the finite element explicit code PAM-STAMP™ to design a formability test for coated thin steel sheets. The tooling and the blank geometries are selected to induce a constant plane strain path leading to a localized necking.

This paper discusses a joint customer-supplier program intended to further develop the ability to design and apply aluminum alloy pistons selectively reinforced with ceramic fibers for heavy duty diesel engines. The approach begins with a comprehensive mechanical properties evaluation of base and reinforced material. The results demonstrated significant fatigue strength improvement due to fiber reinforcement, specially at temperatures greater than 300°C. A simplified numerical analysis is performed to predict the temperature and fatigue factor values at the combustion bowl area for conventional and reinforced aluminum piston designs for a 6.6 liter engine. It concludes that reinforced piston have a life expectation longer than conventional aluminum piston. Structural engine tests under severe conditions of specific power and peak cylinder pressure were used to confirm the results of the cyclic properties evaluation and numerical analysis.

Squeeze casting is, nowadays, the more widely accepted industrial process to produce Aluminum Alloy heavy duty pistons reinforced with short ceramic fibers (FRM). However, rapidly solidified aluminum alloys (RSA) have not yet received much attention as an alternative material for local piston reinforcement, although they have far more strength than the fiber preforms, the starting raw material to produce FRM. The aim of this paper is to show the production routes to manufacture bowl rim reinforced pistons with FRM and RSA, followed by the analysis of some criteria affecting the mechanical properties of FRM (related to the fiber geometry and their chemical reaction with the metal matrix) and of RSA (powder metallurgy versus spray deposition). The resulting macro-interface is also considered as a discontinuity of properties. Finally, some engine test results obtained with pistons reinforced with FRM and RSA are compared with the results obtained on baseline Aluminum Alloy pistons.

A preliminary study was done to select the more adequate composite material to be used as a reinforcement at the combustion bowl of higher output diesel engine pistons. From the three types of composites produced, namely, Ceramic Reinforced Material (CRM) , Metal Reinforced Material (MRM) and Fiber Reinforced Material (FRM) (1)*, FRM was selected after preliminary tests of mechanical properties, machinability and diesel engine tests, realized in a small monocylinder diesel engine.