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Draw bead simulator tests were performed on various tool materials using aluminum alloys 2008-T4 and 6111-T4. The tool materials included hardened cast steel J435/0050A, D2 alloy, cast steel with ion nitride and PVD chromium nitride surface treatments, and cast steel with standard chromium and Wearalloy™ chromium coatings. Friction and galling behavior were monitored over an extended period of testing which allowed differentiation of the tool materials and alloys. Wearalloy™ and CrN tool coatings consistently demonstrated improved ability to prevent material transfer for both aluminum alloys, in spite of friction coefficients which were higher than the uncoated and ion nitrided tools. The ion nitrided surface exhibited the lowest friction coefficients of the surface treatments tested, but showed appreciably more wear. For a given lubricant and dilution ratio, alloy 2008-T4 exhibited an increased tendency for material transfer compared to alloy 6111-T4 for all tool materials tested.

Exhaust manifold thermal reactors, exhaust gas recirculation, exhaust particulate trapping systems, and appropriate engine adjustments have been combined to produce total emission control systems which reduce all gaseous and exhaust particulate emissions from passenger vehicles. The first generation system was developed to meet the former United States and State of California emission standards for 1975. Field service tests demonstrated that the emission standards were met, but unexpected operational problems were encountered. Solutions to these problems have been found. Second generation total emission control systems are being developed in an attempt to meet the current United States emission standards for 1975 - 1976. These systems in their present state of development produce very low exhaust emission levels; the hydrocarbons are well below the standards and the carbon monoxide and nitrogen oxide levels are quite close to the 1975 - 1976 standards.