对截面尺寸为810 mm×1 320 mm的FS2738预硬化塑料模具钢大模块进行理化检验，测定了模块的整体硬度分布，并对不同部位进行了化学成分、夹杂物、显微组织分析。结果表明：整个模块的硬度差 ≤ 2.5 HRC，模块预硬化后显微组织由回火马氏体和回火贝氏体组成，化学成分较均匀，夹杂物含量少，能满足大尺寸塑料制品行业的使用要求。

In different parts of the chemical composition,inclusion and microstructure analysis of size for 810 mm x 1320 mm FS2738 pre-hardened plastic mould steel modules anatomical analysis,determined the overall strength of the module distribution. The results show that the hardness of the entire module difference is less than or equal to 2.5 HRC, module pre hardening after tempering martensite and tempered bainite composition,chemical composition of a uniform,less inclusions,can meet the requirements of large sized plastic products industry.