A sheet material of a copper alloy has a chemical composition including 1.2 to 5.0 wt % of titanium, and the balance being copper and unavoidable impurities, the material having a mean crystal grain size of 5 to 25 μm and (maximum crystal grain size−minimum crystal grain size)/(mean crystal grain size) being 0.20 or less, and the material having a crystal orientation satisfying I{420}/I0{420}>1.0, assuming that the intensities of X-ray diffraction on the {420} crystal plane of the surface of the material and the standard powder of pure copper are I{420} and I0{420}, respectively.