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The history of the development of sheet aluminum wheels, including alloy selection, properties, and tests are discussed. A number of alloys were considered for wheel application. The strain hardening characteristics, the excellent corrosion resistance and other property criteria led to the selection of 5454 as the sheet aluminum wheel alloy

The Reynolds’ 390 engine technology eliminates the need for iron bore liners in aluminum engines. This allows casting of the cylinder block and bores as an integral unit. The technology is a three-part system consisting of the hypereutectic 390 aluminum-silicon alloy, compatible pistons and a special cylinder bore finish. When properly applied, it can produce a lightweight, strong, compact and relatively low-cost aluminum engine block.

Aluminum use for automotive body sheet applications is growing. This growth requires improvement of related joining processes and technology. Resistance spot welding will be one of the major joining technologies used in assembling automobiles. When spot welding aluminum, electrode tip life is limited by tip erosion and pickup of aluminum on the tip. Increasing weld current improves weld strength (to a limit), however this reduces tip life. This study examines the control variables in the resistance spot welding process and offers an improved weld schedule to achieve desired weld properties while maximizing tip life. First, the limits of weld parameters where satisfactory welds can be obtained are determined. A window of tip force and weld current is established for a given material and tip geometry. These limits are used to optimize the weld schedule in terms of tip life. Spot welds fail on the basis of shear strength, button diameter or peel rate.

A new type plated electrode has been developed which shows considerable promise for spot welding mill finish and mechanically cleaned aluminum sheet. This electrode consists of preconditioning the tips of regular Class I and Class II electrodes followed by an inexpensive electroplating of dull nickel. Laboratory data has shown that 2000 spots can be made on mill finished 2036 aluminum using this plated electrode. On wirebrushed 5182-0, 3750 welds were made before failure occurred. This represents a significant increase in tip life compared to tests run using regular copper electrodes. The paper gives details as to how the nickel plated electrodes were developed. This includes results from evaluating other electrode plating and capping materials. The results of tests run using the plated electrodes are included as part of the paper, as well as a discussion as to why the nickel plating works when spot welding aluminum.

High integrity aluminum castings are potential replacements for cast iron in current vehicle weight reduction programs. Domestically, several cast aluminum structural-type components are already realities, saving weight and contributing to improved fuel economy; wheels, brake drums, master brake cylinders and power steering housings. In Europe, suspension components, wheel hubs and disc brake calipers are cast in aluminum for some car models, indicating the functional and economic feasibility of such parts. Alloy and process technology already exist to enable production of realiable, high strength aluminum castings. Domestic automotive product engineers are urged to carefully consider and thoroughly test such aluminum castings along with the many other weight reduction possibilities currently being investigated.

Aluminum castings have much to offer the automotive industry in terms of weight reduction and energy savings. Their long-term acceptability can only be assured, however, by applying the most cost-effective combinations of material and processing. This paper will point out some “cost-saving” opportunities in two basic areas: (1) The use of hypereutectic aluminum-silicon alloys to eliminate a need for ferrous wear-surface inserts, to reduce machining capital expenditures and to reduce overall part weight; and (2) The use of two processing methods, “Pore-Free” die casting and “low-pressure” casting, to produce aluminum parts with minimum metal usage and energy consumption.