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As a result of the wide range of operating environments, component parts of automotive and commercial engine exhaust systems require a unique combination of material properties that are not easily met using existing wrought, cast, or powder metallurgy alloys. Alpha Sintered Metals (ASM) now offers a new Powder Metal (PM) alloy with improved hot oxidation properties that not only supplements the application of traditional stainless steel alloys but also enhances the service life reliability of these components for elevated exhaust temperature applications. ASM's new alloy named Alphaloy, demonstrates material property advantages for several critical exhaust system attributes. The test results of studies comparing Alphaloy to other traditional materials exhibit improved performance relative to hot oxidation resistance, tensile strength and machinability while maintaining consistent performance for thermal expansion, atmospheric corrosion and weldability.

This paper presents the development and applications of engine friction algorithms to quickly estimate performance, optimum geometry of critical engine components, and packaging for rapid engine concept assessments. The development and implementation of some knowledge-based design rules will also be presented to quickly estimate the critical geometry of engine components and component weight such as valve sizing, piston weight, crankshaft geometry, etc. Some examples of powertrain concept design, such as the estimation of friction and packaging will be presented. The simulation results of the friction algorithms will be compared to some of available experimental data and also other friction estimation methods.

PET (Powertrain Engineering Tool) [1, 2] is based on an object-oriented hierarchy system and therefore each component (parent) has its own sub-component (child) systems. Developing explicit forms of objective functions and constraints is simple due to the object-oriented component system of PET. This system automatically recognizes the geometry of components and related design functions in its sub-component levels. This paper discusses computational efficiency, solution accuracy and robustness of software when using closed-form representatives of the derivatives of objective functions and constraints in sequential quadratic programming. Examples of generating closed-form representatives of the derivatives of objective functions and constraints in C/FORTRAN language syntax by using a symbolic processor, Mathematica [3], and mass reduction of the piston-pin are also presented.