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An research vision towards future generation of cars using light
weight materialsDr. Shankar Kalyanasundaram
June 6, 2007
DERF seminar Program
Some facts about automotive use in U.S.A
• Employs millions of people • A vehicle is sold every two seconds – excellent for personal mobility• Paved area equal to the states of Ohio, Indiana and Pennsylvania,
requiring maintenance costing more than $200 million per day• Maimed or injured 250 million people and killed more Americans than
have died in all wars in America’s history• 8 million barrels of oil is used every day• Creates 7 billion pounds of unrecycled scrap and waste every year• Emits lots of greenhouse gases (estimate include one-fourth of U.S
generation of greenhouse gases)
Reference: Natural Capitalism- The next Industrial Revolution; P. Hawken, A.B. Lovins, L.H Lovins
How about efficiency?
• 80% of the fuel consumption is lost mainly in the engine’s heat and exhaust
• Of the resulting force 95% is spent on moving the car and only 5% is spent on moving the driver
• 1% of fuel consumed is actually used in moving the passengers (1 cent for every dollar that one spends on petrol)
What is the answer?
• Needs to be ultra light weight• Needs to have ultra-low-drag behavior• Need a more efficient propulsion system
– Hybrid-electric– Alternate fuels– Fuel Cell Technology
• Need to be fully recyclable• Need to blend in today’s best technology• Need to be commercially viable to produce and provide
the customers with a “real” value for money
Our research focus• Develop a research framework for manufacturing light weight
materials for mass production (stamp forming)– Composite materials– Sandwich structures
• Lightweight materials are currently used in low volume & long production time applications (aerospace)
STAMP Forming of Metals
• High volume production ~ 2 minutes for each part couple of hundreds of parts per shift• Quality indicators Splitting Wrinkling Spring back (Geometrical tolerance)• Generally involves room temperature manufacturing
Research challenges on light weight material forming
• Develop an unified approach that combines numerical (FEA), analytical and experimental work
• The problem is governed by a large number of highly nonlinear coupled equations (FEA)
• Need realistic mechanics models to characterize the material behavior, interfaces and failure behaviors
• We have developed a novel experimental methodology to measure deformation behavior real time during forming – first of its kind in the world for light weight materials
• Major strain for top surface of aluminium cup• Aramis: above• LS DYNA (FEA) : right
• Measurement of surface strain in stamped forms used to validate modeling
Validation of Finite Element Simulations
Key findings so far
• Need to heat the samples before forming • The material combinations can play a very
critical role in producing a defect free part in addition to process variables
• Light weight materials can have superior forming characteristics compared to their monolithic metals --- Yes there is a big future for them in commercial productions!!
• Research is currently underway to produce an unified approach (improved and better than anyone) to handle this important problem in large scale manufacturing