Earth working tool having a working element fabricated from cemented tungsten carbide compositions with enhanced properties
US4859543A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 28, 1987 |
| Grant date | Aug 22, 1989 |
| Priority date | — |
| Expiry date | Apr 28, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12139
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An earth working tool, such as a mining and construction cutter bit, has an elongated body, and a working element, such as a hard tip attached on a forward end of the body. The working element or hard tip is fabricated of a composition of essentially tungsten carbide of large grain size. The composition has one of a plurality of different percents, X, by weight of cobalt as a binder and one of a plurality of different Rockwell A scale hardnesses, Y. The cobalt percents X and hardnesses Y are paired in sets and have nominal values which satisfy the relationship: EQU Y=91-0.62X, where X is selected from within a range of from about 4.2 to 12.0 percent. Also, the values of Y in the sets of X and Y have upper and lower limits which satisfy the respective relationships: EQU Y=91.1-0.57X and Y=90.0-0.67X, where X is selected from the aforementioned range of from about 4.2 to 12.0 percent. More particularly, each composition has one set of cobalt percent X and hardness Y values selected from a plurality of different sets of (X, Y) as follows: (4.5+/-0.3, 88.2+/-0.3), (5.0+/-0.3, 87.9+/-0.3), (8.5+/-0.5, 85.8+/-0.5) and (10.5+/-0.5, 84.5+/-0.6).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.