摘要：Following the oil crisis in the 1970s and consumer awareness of the great harm caused to the environment by motor vehicle emissions, automakers began to overhaul their design criteria with a view to reducing fuel consumption. One of the many solutions adopted has been the extensive use of Aluminum and Magnesium instead of steel and cast iron. This has resulted in great weight savings and hence a reduction in fuel consumption. It has also given Aluminum and Magnesium foundries access to new and attractive markets. In the first substantial applications, namely the fabrication of Aluminum cylinder heads and engine blocks, quality requirements were primarily concentrated on static strength and water and oil tightness, in addition, of course, to dimensional precision.New and important uses are being found for Aluminum alloys: steering knuckles and suspension links, levers and cross members. For these families, the main quality requirements relate to fatigue and impact resistance. New alloys and new manufacturing processes are necessary to ensure that suspension components are endowed with these qualities.The HIP – Hot Isostatic Process has been introduced several years ago has been proven one interesting and effective way of Aluminum treatment to increase fatigue strength. An evolution of the concept, known as Liquid HIP- LHIP, perfected in conjunction with Metal Casting Technology Inc., Idra Presse and Teksid is now coming on stream. It ensures quality levels and trimmed costs difficult to obtain with conventional processes.
