DESIGN AND FABRICATION OF DIE FOR BLOW FORMING
Guided by Mr. VIJAY ANANTH Asst prof.
Submitted by
A.RAMASUNDARESAN :31008114043
A.VIGNESH :31008114304
V.VIJAYABASHKAR :31008114306
E.S.VINOTHKUMAR :31008114307
ABSTRACT:
A stiff competition in the automobile and aerospace industries in recent
times has forced to innovate newer and better technologies for the fast paced
world. Aluminum automotive components made using a hot blow forming
process are reducing vehicle weight and increasing the fuel efficiency of today’s
cars
Al 6063 disks of a super plastic forming grade gas-pressure formed to
hemispheres at constant forming pressures with back pressure. The forming
operation was performed using an in-house designed forming apparatus. The
temporal change of dome heights of the hemispheres were measured for the
different forming and back pressure applied. Forming test with dies were
performed at 5800 C.
INTRODUCTION:
Recent interest in lightweight and inexpensive alloys for transportation
systems has attracted attentions to aluminum – magnesium alloys. Al 6063
alloy , because of its good weld ability , reasonably high corrosion resistance
and high strength with reasonable ductility , has been one of such alloys. Large
ductility required in forming engineering parts with contoured geometry has to
development of superplastic grade of the alloy. Deformation behavior and
microstructural evolution of the superplastic Al 6063 has been extensively
investigated for tensile deformation . the purpose of the present study is to
investigate the deformation behavior of Al6063 alloy using hemispherical dies.
Superplasticity
• Superplasticity in materials is characterized by large neck free elongation under low flow stress when they are formed at temperature exceeding about one half of the melting point.
• Superplastic forming is carried out essentially under isothermal conditions with very low strain rates.
SUPERPLASTIC BLOW FORMING PROCESS:
• It is metal working process for forming sheet metal. It works upon the
theory of superplasticity which means that a material can elongate beyond
100% of its original size.
• It is manufacturing method used for making aluminum automotive
components . Parison is a tube like pipe which is used to pass the argon
gas . The parison is then clamped into the Die and gas pumped into the
mould. Aluminum is heated one third of its melting point and argon
pressure gas is passed and aluminum forms the mould shape.
Superplastic Blow Forming Process
FORMULAσ = k έ m
where,• ‘σ’ is effective flow stress, • ‘έ’ is strain rate,• ‘k’ is constant depends upon temperature and
grain size ‘m’ is strain rate sensitivity index .
LAYOUT OF THE DIE
DESIGN CALCULATION
For the analysis of the superplastic forming behaviour, the disk specimens were
assumed to bulge to spherical membranes of uniform thickness.
An applied pressure, P, In a hemispherical die of results Ro would deform a disk
specimen of the initial thickness T0 Into a spherical membrance of radius p.
By measuring the dome height HD of the membrane, and assuming the volume
constancy of the material, one can calculate the radius p, thickness t, strain e, and shell
stress , of the membrane.
SPECIFICTION
Applied pressure : 25 N/mm2
Initial thickness of Al 6063: 2 mm
Operating temperature: 5800C
Diameter of the hemispherical cavity: 30 mm
Hemispherical die of radius (Ro): 15 mm
Dome Height (HD): 25 mm
1) P =
P =
P = 25 N/mm2
2) t =
t =
t = 1 mm3) = ln = ln
= 0.693 (Compressive in nature)
=312.5 N/mm^2
=
DESIGN CALCUATION
MATERIALS DIMENSIONS QUANTITY
MALE DIE MILD STEEL
DIAMTER=100 mm THICKNESS=25 mm
1
FEMALE DIE MILD STEEL
DIAMETER=100mm THICKNESS=100 mm
1
PARISON TUBE DIAMETER =20 mm 1
ALIGN BOLT 4
BILL OF MATERIALS:
BENEFITS:
Weight saving of 40% on a typical mid size automobile
which reduces green house gas emission and increase fuel
economy.
No color and fit issues on the auto assembly where two
piece construction as become one piece.
simply of auto assembly process.
completive advantage for US industry in manufacturing
light weight automotive components.
Low-cost tooling
Low environmental impacts –non-lead die tubes, low noise
Reduced weight for high fuel efficiency
Improved structural performance
PHOTOGRAPHS:
COMPONENT PRODUCED:
Cost of the project
MATERIALS COST
MALE DIE 400 FEMALE DIE 800
MACHINING 900 BOLT 100
PARISON TUBE WITH 300REDUSER
TOTAL COST 2500
CONCULSION
Thus we have successfully design and fabricated a
die for conducting blow forming tests. Blow forming tests has
been conducted for different pressure and temperatures.
REFERENCES
Super plastic flow phenomenology and mechanics by
kuppuswamyananthapadhmanabhan, R.A. Vasin, F.V.
ENIKEEV.
Super plasticity in metals and ceramics by T.G. Nieh, wads
worth, oleg D . Sherby
psg design data book.