Machinability of disc drums fabricated by hot forging of an AISI 430F stainless steel

摘要

Machinability of disc drums fabricated by hotforging of an MSI 430F stainless steel was investigated in thepresent study. Particular emphasis was placed on a role of themicrostructural change, which mostly 'depended on the annealingconditions after forging. In the forged drum specimens, MnSinclusions were highly elongated, and a considerable amount ofmartensite was found. Three different annealing conditions wereadopted on the forged drum specimens in order to completely orpartly dissolve martensite. The surface roughness tests wereconducted on these specimens and then the test data werecompared via hardness and microstructures. Severely elongatedMnS inclusions deteriorated machinability, but the specimenscontaining martensite showed a good machined surface becausemartensite played a role in free-machining instead of MnSinclusions. These findings suggested that a proper amount ofmartensite formed during forging and annealing would bebeneficial for machining of the 430F stainless steel products.