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Modern automobile diesel engines make use of aluminium cylinder heads that experience both high pressure and thermal loads. Maximum temperatures are above 250°C in the valve bridge area, generating microstructural transformations in the material and thus local evolution of the mechanical properties. To be able to predict the life time of this component with a reasonable amount of confidence, it is therefore necessary to describe these changes in the material. This has been done on a variety of casting materials, with various amount of silicon and copper. Two of them have been taken as references, namely the A356 and 319 type of alloys, making extensive use of Transmission Electron Microscope (TEM) associated with Automatic Image Analysis for quantitative analysis of the precipitation stages during different heat treatments, from the as-received state to saturated aging state.

In the demanding aircraft OEM and repair environment, requirements for success in the area of surface enhancement can be identified as: 1. The ability to produce consistent, repeatable and the highest quality coatings in the most economical manner. 2. A high degree of flexibility, providing the deposition of the widest possible range of coatings onto a large variety of substrate configurations and allowing the user to react quickly to diverse and constantly changing requirements. Plasma spraying with automated equipment meets both of these challenging requirements.

The NASA Office of Exploration (OXEP) was established in June 1987 to provide recommendations and viable alternatives for an early 1990's national decision on a focused program for human exploration of the solar system, particularly of the Moon and Mars. 1 Missions beyond the low earth orbit Space Station Freedom poise new and different challenges for crew life support systems (LSS). Case study missions under consideration will demand careful selection of reliable and efficient LSS technology by the mission planners. This paper describes a study currently underway to develop a Mission Planners LSS Guidebook for providing tabular data, such as weight, volume, and power for comparing various LSS approaches against key drivers derived from mission case studies. These quanitative data facilitate LSS approach selection for any mission of interest bounded by the current OXEP case studies.