PROBLEM TO BE SOLVED: To provide an inexpensive high strength wide flange shape for timbering, excellent in strain aging embrittlement resistance by positively utilizing N as an inexpensive strengthening element. ;SOLUTION: This high strength wide flange shape for timbering excellent in strain aging embrittlement resistance of ≥440 MPa yield strength and ≥590 MPa tensile strength has a composition containing, by weight, 0.10 to 0.20% C, 0.05 to 0.65% Si, 0.9 to 1.8% Mn, 0.008 to 0.018% N, ≤0.05% Al, ≤0.035% P, ≤0.020% S and ≤0.0004% H, moreover containing V satisfying the range in the following inequality (1) in accordance with the N content, and the balance substantially Fe with inevitable impurities, and the carbon equivalent (Ceq) defined by the following formula (2) is ≤0.47, and also, the thickness of a flange if 8 to 14 mm: 0.014+3.6×[%N]≤[%V]≤0.044+3.6×[%N]...(1), and Ceq=[% C]+[%Mn]/6+[%Si]/24+[%Cr]/5+[%Mo]/4+[%Ni]40+[%V]/14...(2).;COPYRIGHT: (C)2001,JPO
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