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Launch load resistant spacecraft mechanism bearings made from niti superelastic intermetallic materials
| Content Provider | NASA Technical Reports Server (NTRS) |
|---|---|
| Author | Moore II, Lewis Chip E. DellaCorte, Christopher |
| Copyright Year | 2014 |
| Description | Compared to conventional bearing materials (tool steel and ceramics), emerging Superelastic Intermetallic Materials (SIMs), such as 60NiTi, have significantly lower elastic modulus and enhanced strain capability. They are also immune to atmospheric corrosion (rusting). This offers the potential for increased resilience and superior ability to withstand static indentation load without damage. In this paper, the static load capacity of hardened 60NiTi 50mm bore ball-bearing races are measured to correlate existing flat-plate indentation load capacity data to an actual bearing geometry through the Hertz stress relations. The results confirmed the validity of using the Hertz stress relations to model 60NiTi contacts; 60NiTi exhibits a static stress capability (3.1GPa) between that of 440C (2.4GPa) and REX20 (3.8GPa) tool steel. When the reduced modulus and extended strain capability are taken into account, 60NiTi is shown to withstand higher loads than other bearing materials. To quantify this effect, a notional space mechanism, a 5kg mass reaction wheel, was modeled with respect to launch load capability when supported on 440C, 60NiTi and REX20 tool steel bearings. For this application, the use of REX20 bearings increased the static load capability of the mechanism by a factor of three while the use of 60NiTi bearings resulted in an order of magnitude improvement compared to the baseline 440C stainless steel bearings.|||| |
| File Size | 1275677 |
| Page Count | 21 |
| File Format | |
| Alternate Webpage(s) | http://archive.org/details/NASA_NTRS_Archive_20150000196 |
| Archival Resource Key | ark:/13960/t9770gr5x |
| Language | English |
| Publisher Date | 2014-05-14 |
| Access Restriction | Open |
| Subject Keyword | Bearings Materials Metals Nickel Alloys Ball Bearings Intermetallics Modulus of Elasticity Ceramics Indentation Stainless Steels Static Loads Titanium Alloys Corrosion Launching Damage Loads Forces Ntrs Nasa Technical Reports Server (ntrs) Nasa Technical Reports Server Aerodynamics Aircraft Aerospace Engineering Aerospace Aeronautic Space Science |
| Content Type | Text |
| Resource Type | Presentation |
