Materials and Crash Testing
Physical Inputs to CAE based ImpactImpact-Crash Simulation Tools
Design Requirements
•
•
•
•
Strain Rate Data Generation, Modelling
and Formatting
600
400
0
0
5
10
15
True Stress (Mpa)
Engineering stress (MPa)
800
200
20
25
0.05
0.1
True Plastic Strain
True Stress (MPa)
0
0.15
0.2
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
•
Precision servo-hydraulic machine with
closed and open loop control features
•
•
Actuator velocity from 1 mm/s up to 20 m/s
Implementation ready material models for
use in commercial finite element tools, and
customised to end user application
•
Fast jaw Technology - acceleration of
complete moving grip before testing starts
•
Material model validation
Stiff 4 column load frame for controlled
testing of components and joined assemblies
•
Development of customer specific test
procedures, instrumentation and specimen
designs for high rate data generation
Velocity profile correction under open loop
control for high speed testing
•
High accuracy data acquisition with logging
frequency of 5 MHz and 12 bit resolution
•
Custom built high frequency force
transducers for high accuracy stress
measurements
•
Local instrumentation fully integrated within
signal conditioning unit e.g. custom built
transducers and special strain gauges
exposed to high speed and large strain
•
Modelling experiment - specimen geometry,
system of measurement and test boundary
conditions
Unique lab facilities, measurement system
and capability to test a wide range of
materials, jointed coupons and components
•
Fast delivery
0
0.00
Controlled strain rate data generation over
seven decades of strain rate up to 1000/s,
conforming to Ford Premium Automotive
Group test procedures, VDEh and IISI
recommendations
•
DP600 strain rate flow curves with IARC fitted surface
30
Engineering Strain (%)
0
High Speed Test Laboratory, Equipment
and Capability
Technical Service
0.20
Material Model Validation
True Plastic Strain
Controlled tensile and compression testing up
to 100 kN static load (160 kN dynamic load)
Medium strain rate specimen design
Joint testing
specimens
10
8
6
4
2
10
20
30
40
50
Strain [%]
0
Application Area of Technology
Reduce time, cost and risk to introduce new
materials to develop new car body designs
•
•
Reduce mass of car body structure
80
14.00
70
12.00
60
10.00
50
8.00
40
30
4.00
End Application of Material Model
20
2.00
0.00
0.037
- strain sensor strain
- strain sensor strain rate
0.0375
0.038
0.0395
Load-Filtered
Actuator0.0385
Position, 0.039
Steel DP600
(2mm), 0.04
Dynamic0.0405
(5 m/s)
10
0
0.041
Time [s]
18
800
20.00
16
18.00
14
700
12
14.00
600
12.00
10
500
Load [kN]
16.00
Improved crashworthiness: compliance to
world wide crash regulation, NCAP, insurance
and pedestrian safety requirements
•
90
16.00
6.00
Strain [%]
•
Improved confidence and efficiency in
application of virtual testing technology to
product development
100
18.00
0
Actuator Displacement (mm)
•
20.00
10.00
8
400
8.00
6
6.00
Machine Mounted Force Sensor Output
4
4.00
- machine Specimen
dynamic
sensor
Mounted force
Force Sensor
Output
- specimen transducer
2.00
2
Strain Rate [1/s]
Measured Force (kN)
Material testing
specimen
5000 mm/s
2000 mm/s
800 mm/s
100 mm/s
10 mm/s
12
Strain Rate [1/s]
Grip speed of 5 m/s: Gauge length 60 mm
14
300
200
0.00
100
0
0.02225 0.0223 0.02235 0.0224 0.02245 0.0225 0.02255 0.0226 0.02265 0.0227
0
Dr. Paul Wood
Mobile: +44 (0)7932 608084
Email: P.K.C.Wood@warwick.ac.uk
Eco-friendly technology
Copyright 2008
LVDT Actuator
Position [mm]
Time [s]
Dr. Claus Schley Dipl.-Ing., PhD
Mobile: +44 (0)7932 729053
Email: Claus.Schley@warwick.ac.uk