Forming stable welded joints between dissimilar metals
US4702406A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 1986 |
| Grant date | Oct 27, 1987 |
| Priority date | — |
| Expiry date | Oct 16, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12937
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method of forming a stable welded joint between low alloy steels and austenitic stainless alloy steels which is characterized by increased resistance to chemical corrosion and mechanical stress and which has a greatly extended service lifetime. The method comprises forming a deposit of a low alloy steel containing niobium onto a portion of low alloy steel to be welded; heating the deposit to a first temperature at which all carbides present therein have dissolved; quenching the deposit and forming a solid solution of the elements of the dissolved carbides; and reheating the deposit for a time period and at a second temperature sufficient to form niobium carbides therein containing substantially all of the carbon present in the deposit. The austenitic stainless steel portion is welded to the deposit using a substantially nonferrous nickel-based alloy as the weld filler material, thereby joining the low alloy steel portion to the austenitic stainless steel portion.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.