Laboratory Studies of Low-Chromium and Chromium-Free Steels for Suspension Coil Springs

AISI 5160 and modified 5160, the most commonly used steels for automotive suspension coil springs, contain chromium. In the event this metal becomes hard to get, our industries should have the information basis for introducing spring steels with less or no chromium. This paper reviews existing spring-steel grades and summarizes a laboratory study aimed at finding new alloys with an optimum combination of properties. New alloy approaches that are potentially competitive with 5160 and modified 5160 during normal times are identified as well as substitutes that could be used during an emergency.