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:
Nov. 05, 2002
Filed:
Sep. 26, 2000
Koji Watari, Kobe, JP;
Yasutaka Okada, Nara, JP;
Sumitomo Metal Industries, Ltd., Osaka, JP;
Abstract
The present invention is directed to a steel product for machine structural use having excellent machinability and to a structural steel part for machinery manufactured from the steel product. More particularly, the invention is directed to a steel product for machine structural use having excellent machinability, particularly bringing about excellent “drill life” and exhibiting excellent “chip disposability” in the course of drilling, as well as to a structural steel part for machinery manufactured from the steel product. The steel product for machine structural use has a chemical composition comprising, in mass percent, C: 0.05% to 0.55%; Si: 0.50% to 2.5%; Mn: 0.01% to 2.00%; P: not greater than 0.035%; S: 0.005% to 0.2%; N: not greater than 0.0150%; elements to be added as needed: Cu, Ni, Cr, Mo, V, Nb, Ti, B, Al, Bi, Ca, Pb, Te, Nd, and Se; −23C+Si(5−2Si)−4Mn+104S−3Cr−9V+10≧0; 3.2C+0.8Mn+5.2S+0.5Cr−120N+2.6Pb+4.1Bi−0.001&agr; +0.13&agr;≧3.0; and balance: Fe and incidental impurities; percentage of ferrite in microstructure being 10% to 80%; and Hv hardness being 160 to 350. In the above expressions, &agr; represents the area percentage in % of a ferrite phase in the microstructure. The structural steel part for machinery can be manufactured relatively easily from the steel product for machine structural use through machining.