The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 27, 1987
Filed:
Oct. 16, 1986
Dennis Sullivan, Raleigh, NC (US);
Richard J Bloch, Raleigh, NC (US);
Carolina Power & Light Company, Raleigh, NC (US);
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.