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:
Dec. 18, 2012
Filed:
Apr. 23, 2009
Katsuhisa Yamauchi, Chiba, JP;
Yasushi Kato, Chiba, JP;
Takumi Ujiro, Chiba, JP;
Takako Yamashita, Chiba, JP;
Katsuhisa Yamauchi, Chiba, JP;
Yasushi Kato, Chiba, JP;
Takumi Ujiro, Chiba, JP;
Takako Yamashita, Chiba, JP;
JFE Steel Corporation, , JP;
Abstract
A material for brake discs has temper softening resistance sufficient to maintain a hardness of HRC 31 or more after tempering at 700° C. for one hour. The low-carbon martensitic chromium-containing steel contains 0.02% to 0.10% of carbon and 0.02% to 0.10% of nitrogen, the total content of carbon and nitrogen being 0.08% to 0.16%; 0.5% or less of silicon; 0.1% or less of aluminum; 0.3% to 3.0% of manganese; 10.5% to 13.5% of chromium; 0.05% to 0.60% of niobium and 0.15% to 0.80% of vanadium, the total content of niobium and vanadium being 0.25% to 0.95%; 0.02% to 2.0% of nickel; and 1.5% or less of copper, and has an Fp value (=−230C+5Si−5Mn−6Cu+10Cr−12Ni+32Nb+22V+l2Mo+8W+10Ta+40A1−220N) of 80.0 to 96.0, a hardness after quenching of HRC 31 to 40, and a hardness after tempering at 700° C. for one hour of HRC 31 or more.