开发的模具钢718(%:0.32~0.40C、0.30~0.50Si、1.00~1.50Mn、≤0.016P、≤0.005S、1.50~2.00Cr、0.40~0.50Mo、0.80~1.20Ni、0.020~0.045Al)198~308 mm厚板的生产工艺流程为90~100 t EAF-LFVD-40 t电渣重熔(950 mm×2 000 mm板坯)-轧制(控冷)-热处理。检验结果表明
钢中的P为0.009%~0.012%
S为0.001%~0.003%
钢中气体含量为(45~60)×10
-6
[N
]
1.5×10
-6
[H
]
(13~18)×10
-6
[O
]
;钢板平均HB值为317~352
其组织为回火贝氏体+少量回火索氏体
满足各类模具的加工和表面质量要求。
Abstract
The production process flow sheet for 198 〜308 mm heavy plate of developed die steel 718 ( % : 0.32〜0.40C
0.30~0.50Si
1.00~1.50Mn
≤0.016P
≤0.005S
1.50~2.00Cr
0.40-0.50Mo
0.80~1.20Ni
0.020-0.045Al) is 90 ~ 100 t EAF-LF-VD-40 t ESR (950 mm x 2 000 mm slab) -rolling (control cooling) -heat treatment. Examination results show that the P content in steel is 0.009%~0.012%
the S content is 0.001%~0.003%
and the gases contents are (45~60) x 10
-6
[N
]
1.5 x 10
-6
[ H
]
and (13~18) x 10
-6
[O
]
; the average value of HB hardness is 317~352 with structure of tempered bainite + minor tempered sorbite to meet the requirement of workability and surface quality for various dies.