Control rods and method of producing same
US4451428A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 1981 |
| Grant date | May 29, 1984 |
| Priority date | — |
| Expiry date | Jan 2, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E30/30
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A control rod for a boiling-water reactor having blades arranged in the form of a cross in transverse cross section includes a plurality of poison tubes disposed therein. Boron carbide powder which is a neutron absorbing material causing an (n, .alpha.) reaction to take place is charged in the poison tubes. The control rod has plates of Hf-Zr alloy arranged in the blades in a position nearer to a forward end of the control rod at which the control rod is inserted in a reactor core than the poison tubes. The plates of Hf-Zr alloy are formed of an alloy of Hf having a large neutron absorption cross section and Zr having a small neutron absorption cross section. The concentration of Hf in the plates of Hf-Zr alloy is successively reduced in going from an end thereof adjacent the poison tubes toward and end thereof at the inserting end of the control rod. The plates of Hf-Zr alloy and the poison tubes have the same neutron absorbing capacity at the boundary therebetween at which they are in contact with each other.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.