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:
Jul. 25, 2006
Filed:
Apr. 28, 2003
Ryoji Hayashi, Himeji, JP;
Makoto Iguchi, Himeji, JP;
Ryoji Hayashi, Himeji, JP;
Makoto Iguchi, Himeji, JP;
Sanyo Special Steel Co., Ltd., Hyogo-Ken, JP;
Abstract
Disclosed is a production process of a steel product for induction hardening and a steel product for carburizing, having improved grain size properties and machinability. This production process comprises the steps of: providing an ingot or bloom comprising a steel comprising, by weight, carbon (C): 0.10 to 0.45% or 0.25 to 0.70%, silicon (Si): 0.03 to 1.0%, manganese (Mn): 0.2 to 2.0%, titanium (Ti): 0.05 to 0.2%, aluminum (Al): 0.005 to 0.05%, and nitrogen (N): not more than 0.01% with the balance consisting of iron (Fe) and unavoidable impurities; and subjecting the steel ingot or bloom to a series of hot working steps including the step of rolling the steel ingot or bloom into a semi-finished steel product, the step of rolling the semi-finished steel product into a steel bar or wire rod, and the step of forging the steel bar or wire rod into a product. In the above series of hot working steps, the steel is given a thermal history in which said steel is at least once heated to 1,250° C. or above, is cooled to room temperature, and is then reheated to a temperature range of 800 to 1,100° C.