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Resilient and corrosion-proof rolling element bearings made from superelastic ni-ti alloys for aerospace mechanism applications
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Padula, Santo A. Noebe, Ronald D. Stanford, Malcolm DellaCorte, Christopher |
| Copyright Year | 2011 |
| Description | Mechanical components (bearings, gears, mechanisms) typically utilize hard materials to minimize wear and attain long life. In such components, heavily loaded contact points (e.g., meshing gear teeth, bearing ball-raceway contacts) experience high contact stresses. The combination of high hardness, heavy loads and high elastic modulus often leads to damaging contact stress. In addition, mechanical component materials, such as tool steel or silicon nitride exhibit limited recoverable strain (typically less than 1 percent). These material attributes can lead to Brinell damage (e.g., denting) particularly during transient overload events such as shock impacts that occur during the launching of space vehicles or the landing of aircraft. In this paper, a superelastic alloy, 60NiTi, is considered for rolling element bearing applications. A series of Rockwell and Brinell hardness, compressive strength, fatigue and tribology tests are conducted and reported. The combination of high hardness, moderate elastic modulus, large recoverable strain, low density, and intrinsic corrosion immunity provide a path to bearings largely impervious to shock load damage. It is anticipated that bearings and components made from alloys with such attributes can alleviate many problems encountered in advanced aerospace applications. |
| File Size | 4078045 |
| Page Count | 24 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20110016524 |
| Archival Resource Key | ark:/13960/t6838sp7v |
| Language | English |
| Publisher Date | 2011-08-01 |
| Access Restriction | Open |
| Subject Keyword | Mechanical Engineering Rockwell Hardness Hardness Tests Bearings Compressive Strength Modulus of Elasticity Fatigue Tests Titanium Alloys Gears Wear Shock Loads Silicon Nitrides Loads Forces Tribology Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Technical Report |
