Page 453 - 04. Subyek Engineering Materials - Manufacturing, Engineering and Technology SI 6th Edition - Serope Kalpakjian, Stephen Schmid (2009)

Bibliography 433

Because of the relatively thin materials used, springback, buckling, and wrinkling
are significant problems in sheet forming. Springback is a function of the yield
stress, the elastic modulus, and the ratio of bend radius to thickness. These prob-
lems can be reduced or eliminated by proper tool and die design, by minimizing
the unsupported length of the sheet during processing, and by controlling the
thickness of the incoming sheet and its mechanical properties.
Among important developments is the superplastic forming of diffusion-bonded
sheets. The process is capable of producing complex sheet-metal structures, par-
ticularly for aerospace applications (which require particularly high stiffness-to-
weight ratios).
Several test methods have been developed for predicting the formability of sheet
metals. In bending operations, the tensile reduction of the area of the sheet gives
an indication of its bendability (minimum bend radius); this also applies to, the
spinnability parameter of metals (maximum reduction in thickness per pass).
For general stamping operations, forming-limit diagrams are very useful, because
they establish quantitative relationships among the major and minor principal
strains that limit safe forming. For deep-drawing operations, the important pa-
rameter is the normal or plastic anisotropy of the sheet (the ratio of width strain
to thickness strain in tensile testing).

KEY TERMS

Beading Drawbead Laser forming Redrawing
Bendability Drawing Limiting drawing ratio Roll forming
Bend allowance Earing Liider’s bands Rubber forming
Bending Electrohydraulic forming Magnetic-pulse forming Shaving
Blankholder Embossing Microforming Shearing
Blanking Explosive forming Minimum bend radius Slitting
Bulging Fine blanking Nesting Spinning
Burnished surface Flanging Nibbling Springback
Burr Formability Normal anisotropy Steel rule
Clearance Forming-limit diagram Peen forming Stretch forming
Compound dies Hemming Planar anisotropy Superplastic forming
Deburring Honeycomb structures Plastic anisotropy Tailor-welded blanks
Deep drawing Hydroform process Press brake Transfer dies
Dent resistance Incremental forming Progressive dies Wrinkling
Dimpling Ironing Punching

BIBLIOGRAPHY

ASM Handbook, Vol. 14B: Metalworking: Sheet Forming, Gillanders, ]., Pipe and Tube Bending Manual, FMA
ASM International, 2006. International, 1994.
Benson, S., Press Brake Technology, Society of Manufacturing I-Iosford, WF., and Caddell, R.M., Metal Forming:
Engineers, 1997. Mechanics and Metallurgy, 3rd ed., Cambridge, 2007.
Boljanovic, V., Sheet Metal Forming Process and Die Design, Hu, ]., Marciniak, Z., and Duncan, ]., Mechanics of Sheet
Industrial Press, 2004. Metal Forming. Butterworth-Heinemann, 2002.
Davies, G., Materials for Automobile Bodies, Butterworth- Pearce, R., Sheet Metal Forming, Springer, 2006.
Heinemann, 2003. Progressive Dies, Society of Manufacturing Engineers, 1994.
Fundamentals of Tool Design, 5 th ed., Society of Manufactur- Rapien, B.L., Fundamentals of Press Brake Tooling, Hanser
ing Engineers, 2005. Gardner, 2005.