| 要約: | In this work, formation of mini gear with superplastic deformation on boronized duplex
stainless steel (DSS) was studied through the employment of these quantifying factors,
i.e. strains and strain rates. As received DSS specimen was thermo-mechanically treated
by heating up to 1537K, holding for one hour, followed by water quenching and then
cold rolled to a plate through a reduction area of 75%. Boronizing process was carried
out at 1223K for 6 hours, thereafter successfully created surface hardness of 2253HV
and 40μm thickness of boronized layer on the DSS. The specimen was then
superplastically deformed into a mini gear at 1223K. Result shows surface integrity of
the boronized layer deformed at 6 x 10-5 s-1 strain rate and 0.4 mm/mm strain was
maintained. As the study progressed, boronized layer demonstrated failure to withstand
the increased load when deformed at 1x 10-4 s-1 strain rate. At 6 x 10-5 s-1 strain rate and
1.0 mm/mm strain, the surface disintegrity was associated to high strain factor.
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