Lead-free shot formed by liquid phase bonding
US5950064A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 17, 1997 |
| Grant date | Sep 7, 1999 |
| Priority date | — |
| Expiry date | Jan 17, 2017 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB22F2998/10
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
There is provided a lead-free projectile, such as a bullet or a ballistic shot, formed by liquid phase sintering or liquid phase bonding of a first particulate having a density greater than lead, a second, ductile, particulate having a melting temperature in excess of 400.degree. C. and a binder having a fluidity temperature that is less than the melting temperature of the second particulate. Unlike solid phase sintering that tends to produce articles having a porosity of about 20%, by volume, liquid phase sintering and liquid phase bonding achieve close to 0% porosity. Reducing the porosity level decreases the amount of high density, first particulate, required to achieve a density close to that of lead. Since the high density particulate tends to be the most expensive component of the projectile, this significantly reduces the cost of the projectile. The reduced porosity also allows for an increase in the amount of the second, ductile, component. Increased ductility generates a projectile with a reduced likelihood of fragmentation on being fired from a weapon and with better deformation on impact with a target. One suitable composition for the projectile is ferrotungten-iron-zinc…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.