Design Considerations for Resilient Rolling Element Bearings Made From Low Modulus Superelastic Materials

Nickel-titanium based superelastic materials are emerging as candidates for rolling element-bearing applications [1]. When properly prepared, these unique intermetallics are hard, exhibit excellent tribological properties and are intrinsically corrosion immune [2]. In addition, recent investigations have revealed that, unlike traditional bearing steels, superelastics can endure much higher levels of recoverable elastic strain during compressive deformation [3]. This behavior enables bearings that are more resilient to load induced damage such as raceway denting and from the ingestion of hard particles. Despite these positive attributes, these alloys differ significantly from conventional steels and these differences must be carefully considered to achieve successful applications. These differences include reduced elastic modulus, high hardness and enhanced resistance to indentation loads. The current paper introduces nickel-titanium based superelastic bearing materials and compares their properties to current bearing materials. General bearing design practices and manufacturing processes are also examined to identify and explore the challenges and opportunities for making resilient rolling element bearings utilizing this new class of superelastic materials.Copyright © 2011 by ASME