基于可锻铸铁的特点，成功开发了可锻铸铁多段加热热处理工艺。该工艺可使可锻铸铁铸件石墨化退火时间节约50%左右，获得了石墨核心多晶粒细小均匀分布，碳化物消除彻底的显微组织；产品综合力学性能超过了现行国际标准的性能指标，在现行国际及ISO5922－81《可锻铸铁》标准的基础上可增加KTH400－12和KTZ750－02两个牌号；经该工艺处理的线路工具、铁路管件、汽车发动机活塞等产品性能良好、质量可靠。

Based on the characteristic of malleable iron, the technology of multistage heat treatment for malleable iron was investigated successfully. Compared with the present technology, the time of graphitizing annealing using new process was saved about 50% . The microstructure, with uniform distribution of fine polycrystal of graphite nuclei and full elimination of carbide, was obtained. Comprehensive mechanics performance of product exceeded that of present international standard . Two brands of KTH400 — 12 and KTZ750 - 02 can be added on the base of present international and “malleable iron” standards. Those products, such as line tool, pipe fitting for railway, engine piston of car etc, with better performances and credible qualities treated by the technology, were welcomed by users.