open access

https://hdl.handle.net/2115/76342

Effect of Carbon Content on the Reaction Behavior of Hot Dipped Carbon Steel in Molten Zn-6mass%Al Bath

日本語

Alloy Layer

2002-02-01

表面技術協会

Journal of the Surface Finishing Society of Japan

53(2)

129-133

The phases and microstructure of the alloy layer formed during hot dipping of carbon steels in molten Zn-Al bath were investigated. Pure iron, 0.2%C and 0.82%C steels and 2.45%C cast iron were used. A plate shape specimen of 300μm in thickness was firstly hot dipped in a molten Zn bath for 3s and then hot dipped in a molten Zn-6mass%Al alloy bath for certain times, and quenched with water. The microstructure of the quenched specimen was observed by using a SEM, and change in thickness of the specimen was measured by using a laser microscope. The pure iron specimen was entirely changed to an intermetallic compound of Fe2Al5(Zn) phase after 1.2ks hot dipping. The thickness of 0.2%C steel specimen was decreased linearly with the dipping time after an early non-reaction period, and 2/3 of the specimen was changed to the Fe2Al5(Zn) phase after 3.6ks hot dipping. It was observed that primarily precipitated ferrite phase preferentially reacted and pearlite structure scarcely reacted. The reacted thickness of the 0.82%C steel and cast iron specimens were only several μm after 86.4Ks hot dipping. In the cast iron specimen, cementite reacted with Al and an Al3C4 phase was formed. The growth of the alloy layer was restricted by the Al3C4 phase. A heat-treated 0.2%C steel specimen with sorbite structure also exhibited the same low reaction behavior as the 0.82% C steel due to homogenized ferrite + cementite structure.

学術雑誌論文

Version of Record

0915-1869

1884-3409

AN1005202X