A MULTIPLE PHASE COMPLEX CAST STEEL COMPOSITION OF HIGH HARDNESS DISC CUTTER RING FOR USE IN TBM AND THE MAKING METHOD THEREOF

摘要

PURPOSE: A manufacturing method of a disk cutter ring for TBM is provided to minimize the abrasion and damage of the cutter, improve the impact resistance, and reduce the abrasion. CONSTITUTION: A manufacturing method of a disc cutter ring for TBM performs the following step. For the total weight of the whole composition, B 0.01-0.03wt% is further included for the Si 0.3wt%, Mn 1.3wt%, V 1.0wt%, C 0.3-0.45wt% and Mo 2wt%. By using the multiple phase complex steel hardening composition comprised of the remainder Fe, the shape of the disk cutter ring is made by molding and the thermal process is executed. The thermal process is comprised of a releasing process which is maintaining three hours at 930C, a quenching process which is maintaining three hours at 860C, and a salt bath quenching thermal process which includes a salt bath process which maintains two hours at 290C after cooling and then cooling again. [Reference numerals] (AA) Hardness HRc; (BB) Casting (before heat treatment); (CC) After heat treatment