Abstract: The invention relates to a method for method for formation of expanded austenite and/or expanded martensite by solution hardening of a cold deformed workpiece of a passive alloy, which method comprises a first step of dissolving at least nitrogen in the workpiece at a temperature T1, which is higher than the solubility temperature for carbide and/or nitride and lower than the melting point of the passive alloy, and a subsequent second step of dissolving nitrogen and/or carbon in the work piece at a temperature T2, which is lower than the temperature at which carbides and/or nitrides form in the passive alloy. The invention further relates to a member, such as a lock washer for securing bolts or nuts prepared using the method.
Type:
Grant
Filed:
April 27, 2012
Date of Patent:
February 21, 2017
Assignee:
EXPANITE A/S
Inventors:
Thomas Lundin Christiansen, Thomas Strabo Hummelshoj, Marcel A. J. Somers
Abstract: A method of activating an article of passive ferrous or non-ferrous metal by heating at least one compound containing nitrogen and carbon, wherein the article is treated with gaseous species derived from the compound. The activated article can be subsequently carburized, nitrided or nitrocarburized in shorter time at lower temperature and resulting superior mechanical properties compared with non-activated articles and even articles of stainless steel, nickel alloy, cobalt alloy or titanium based material can be carburized, nitrided or nitrocarburized.
Type:
Grant
Filed:
July 19, 2010
Date of Patent:
September 30, 2014
Assignees:
Expanite A/S, Danmarks Tekniske Universitet—DTV
Inventors:
Thomas Lundin Christiansen, Thomas Strabo Hummelshøj, Marcel A. J. Somers
Abstract: The invention relates to a method for method for formation of expanded austenite and/or expanded martensite by solution hardening of a cold deformed workpiece of a passive alloy, which method comprises a first step of dissolving at least nitrogen in the workpiece at a temperature T1, which is higher than the solubility temperature for carbide and/or nitride and lower than the melting point of the passive alloy, and a subsequent second step of dissolving nitrogen and/or carbon in the work piece at a temperature T2, which is lower than the temperature at which carbides and/or nitrides form in the passive alloy. The invention further relates to a member, such as a lock washer for securing bolts or nuts prepared using the method.
Type:
Application
Filed:
April 27, 2012
Publication date:
February 20, 2014
Applicant:
EXPANITE A/S
Inventors:
Thomas Lundin Christiansen, Thomas Strabo Hummelshoj, Marcel A.J. Somers
Abstract: A method of activating an article of passive ferrous or non-ferrous metal by heating at least one compound containing nitrogen and carbon, wherein the article is treated with gaseous species derived from the compound. The activated article can be subsequently carburised, nitrided or nitrocarburised in shorter time at lower temperature and resulting superior mechanical properties compared with non-activated articles and even articles of stainless steel, nickel alloy, cobalt alloy or titanium based material can be carburised, nitrided or nitrocarburised.
Type:
Application
Filed:
July 19, 2010
Publication date:
May 10, 2012
Applicant:
EXPANITE A/S
Inventors:
Thomas Lundin Christiansen, Thomas Strabo Hummelshøj, Marcel A. J. Somers