Hybrid Incremental Forming: Investigation on Localized …
159
Fig. 7 Thickness profiles of
conical frustum formed at
10 mm P d
plastic defamation is spread over large area as compared bending deformation due
to 70 mm preform tool radius. The bending deformation causes thickness reduction
in the 1st stage of HISF process. In the second stage, more thickness reduction due
to SPIF process is observed.
Finally, it is observed that the developed HISF process forms parts in short time
period as compared to SPIF process. In HISF process, preforming operation forms
the partial shape of the part to be formed. Hence, HISF requires slightly less time to
form the part.
4 Conclusion
In present experimental work, a hybrid incremental sheet metal forming method is
developed for forming conical frustums. Findings of present work are summarized
as follows:
1. Stretching has considerable influence on thickness distribution and localized
thinning in formed parts. More stretching induces more plastic deformation,
which results in increased local thinning.
2. HISF process results in improved thickness at thinning band which appears near
clamped edge.
3. Preform tool radius has a significant influence on thickness distribution of parts
formed using HISF process. 70 mm stretching tool radius and 10 mm stretching
results in reduction in minimum thickness as well as results in uniform thickness
distribution in the formed part.
4. Process combination of preforming and SPIF process leads to short forming
cycles as compared to SPIF alone.
159
Fig. 7 Thickness profiles of
conical frustum formed at
10 mm P d
plastic defamation is spread over large area as compared bending deformation due
to 70 mm preform tool radius. The bending deformation causes thickness reduction
in the 1st stage of HISF process. In the second stage, more thickness reduction due
to SPIF process is observed.
Finally, it is observed that the developed HISF process forms parts in short time
period as compared to SPIF process. In HISF process, preforming operation forms
the partial shape of the part to be formed. Hence, HISF requires slightly less time to
form the part.
4 Conclusion
In present experimental work, a hybrid incremental sheet metal forming method is
developed for forming conical frustums. Findings of present work are summarized
as follows:
1. Stretching has considerable influence on thickness distribution and localized
thinning in formed parts. More stretching induces more plastic deformation,
which results in increased local thinning.
2. HISF process results in improved thickness at thinning band which appears near
clamped edge.
3. Preform tool radius has a significant influence on thickness distribution of parts
formed using HISF process. 70 mm stretching tool radius and 10 mm stretching
results in reduction in minimum thickness as well as results in uniform thickness
distribution in the formed part.
4. Process combination of preforming and SPIF process leads to short forming
cycles as compared to SPIF alone.