Nippon Steel & Sumitomo Metal Corp , Japan's biggest steelmaker, said on Thursday its first-half recurring profit rose 1.5 percent as lower material costs boosted margins and offset appraisal losses on its high-priced stockpiles. The world's No.2 steelmaker by output stuck to its full-year forecast of 400 billion yen in recurring profit, which is pre-tax before one-off items, compared with the 403.77 billion yen mean estimate of 16 analysts polled by Thomson Reuters I/B/E/S.