| 摘要 |
<p>PURPOSE: A pre-hardened steel for a mold for plastic molding is provided to maintain corrosion resistance, thermal conductivity and mirror-surface finishing properties. CONSTITUTION: A pre-hardened steel for a mold for plastic molding comprises 0.09-0.13 weight% of C, 0.20-0.40 weight% of Si, 0.40-0.60 weight% of Mn, 0.100 weight% of P, 2.0-3.00 weight% of Cr, 0.60-0.90 weight% of Cu, 2.00-2.45 weight% of Ni, 0.20-0.40 weight% of Mo, 0.09 weight% or more of Mo/Ni, 0.60-0.90 weight% of Al, 0.0100 weight% of O, 0.0100 weight% of N, residual Fe and unavoidable impurities. The pre-hardened steel for a mold for plastic molding additionally contains one or more elements selected from 0.001-0.10 weight% of S, 0.001-0.3 weight% of Se, 0.001-0.3 weight% of Te, 0.0002-0.10 weight% of Ca, 0.001-0.20 weight% of Pb, and 0.001-0.30 weight% of Bi. [Reference numerals] (AA) Mo[weight%]; (BB) Ni[weight%]</p> |
