development and optimization of a lower control arm (lca) using high strength steels
DESCRIPTION
The significance of high-strength steel concepts for vehicle parts has increased in the last years due to the meeting of reduction in weight and enhanced safety requirements. However these steels have high strength values , this feature is not adequate to reduce the weight of chasis parts due to the reason that weld zones have a limited strength without depending on the strength of steel. This case is a major problem in terms of fatigue requirements. OEMs usually prefer forged lower control arms as well as the control arms which consist of welded two or more parts on the commercial vehicles. Reduction of stresses on weld zones is one of the targets. Lower control arms are mostly manufactured from forged , cast and sheet steels and absorb the loads such as braking , acceleration, lateral , longitudinal. In this study , a lower control arm (LCA) for a light-commercial vehicle is designed by welding of double metal sheets. LCA design has been analyzed on FEA softwares in order to obtain linear and nonlinear test requirements by using inertia relief option , tensile test requirements by using rubbers.TRANSCRIPT
DEVELOPMENT AND OPTIMIZATION OF A LOWER CONTROL ARM (LCA) USING HIGH STRENGTH STEELS
European Altair Technology Conference- Munih June 2014
Metin Çallı, Mesut Kaya , Emre Yiğitoğlu , Nihal Efe
AGENDA
ABOUT US
LCAs AT A GLANCE
BENCHMARKING
FE ANALYSISES
RESULTS & COMMENTS
M.Kemal Coşkunöz
60 YEARS EXPERIENCE IN METAL FORMING
COŞKUNÖZ HOLDING
R&D CENTER MANAGEMENT
AUTOMOTIVE TEAM
AUTOMATION TEAM
MACHINERY TEAM
FINITE ELEMENT ANALYSIS
PRODUCT DEVELOPMENT
MATERIAL DEVELOPMENT
TEST
& PROTOTYPE
INTELLECTUAL PROPERTIES
LASER CUTTING
3D MACHINES 2D MACHINES
LASER WELDING
SIMULATION
PROCESS DEVELOPMENT
TOOL & DIE DESIGN
CAM
NC CNC PLC
HMI
ROBOTIC APPLICATIONS
LASER TECHNOLOGIES
TEAM
TOOL & DIE TEAM
PRODUCT DEVELOPMENT
PRESS MACHINES AND
REFURBISHMENT
COŞKUNÖZ R&D CENTER
DOCUMENTATION
Reverse Engineering
Computer Aided Design Test Verification
Prototyping
Computer Aided Analysis
CAPABILITIES
Optimization
Benchmarking Data Acquisition
MACHINERY
TEAM
LASER
TECHNOLOGIES
TEAM
AUTOMATION
TEAM
TOOL & DIE
TEAM
AUTOMOTIVE
TEAM
(12)
71
CAPABILITIES
Human Resources Software Resources
DESIGN Catia V5 – 32 licenses SolidWorks - 14 licenses UniGraphics - 1 license
FORMING
Autoform Hyperform
FEA
HyperMesh Radioss Optistruct (Optimization) Acusolve CFD
KINEMATIC ANALYSIS
Expressus
BENCHMARK
A2MAC1
Magnesium IP Beam
TWIP Door Impact Beam TWIP Roll Forming
Martensitic Roof Reinforcement Bar
CFRP Composite Side Impact Beam
CFRP Composite Suspension Parts
CP Salıncak Kolu
TRIP Tünel Sacı
CFRP Composite
+
DP Bumper Beam
Martensitic Side Impact Beam
22MnB5 and 22MnV6 Rear Axle Beam
CP Lower Control Arm
Aluminium Hood Reinforcement
CAPABILITIES
Right Lower Control Arm Right Lower Control Arm
Front Bush
Rear Bush
Steering Knuckle
Lower control arms are mostly manufactured from forged , cast and sheet steels and absorb the loads such as braking , acceleration, lateral , longitudinal.
LOWER CONTROL ARM AT A GLANCE
Tire Volume Steering Knuckle Cross Member
Stabilizer Torque Wrench Rod Boot
L.C.A. AT A GLANCE
Rear Bush Zone
Front Bush Zone
Ball Joint
L.C.A. AT A GLANCE
Forged Steel One-Sided Steel
Welded Metal
Forged Aluminium
Ball Joint
Riveting
Bushing Installation to Flanged Hole
Welded Tube for Reinforcement
Ball Joint Connection with Bolts
BENCHMARKING
Bending operation, one-sided steel control arm Reinforcement Bracket
Ball joint, riveting , weld connection
BENCHMARKING
FB 540 M 800 HY / CP 800
TRIP 800 SPHN 590C / DOMEX 600
BENCHMARKING
BENCHMARKING
Ford Transit Ford Connect
Control Arms produced by Coşkunöz
Honda Civic
BENCHMARKING
F2
F1
F3
Steering Loads
Vertical Acceleration Loads
Braking Loads
Braking During Steering Loads
Reverse Acceleration Loads
Longitudinal Acceleration Loads
DESIGN INPUTS / FORCES
After definition of packaging data for LCA , design and nondesign zones have been defined and modelled on Hypermesh by using critical load conditions.
TOPOLOGY OPTIMIZATION
Design Area
Non-design
Area
As a result of optimization , that the area marked with 1 have been protected and it is so significant has been seen . Additional to this , it has been identified that excessive material in the area 2 is unnecessary.
TOPOLOGY OPTIMIZATION
1
2
Buttom Plate 700 MPa
Upper Plate 700MPa
Forge
Forge
Forge
Reinforcement tube
LINEAR ANALYSISES
Reinforcement tube has been used to reduce the stresses around the mounting hole .
Representative Picture to show the reinforcement effect on stresses
Reinforcement Tube
LINEAR ANALYSISES
Nonlinear analysises have been investigated in two different sections as with rubbers and without rubbers . Goal in nonlinear analysises without rubbers is that LCA must provide plastic deformation requirements after unloading .
F2
F1
F3
Extrapolated Rubber Test Data have been used on FEA software.
NONLINEAR ANALYSISES
A Lower Control Arm must meet the requirements for energy absorption , durability and fatigue. In our study , a material which has high strength value , high weldability and high fatigue resistance has been choosen.
MATERIAL SELECTION
As a result of nonlinear analysises and optimization studies for definition of ideal geometry and material , it has been seen that plastic strains occured on the close zone to cross member.
NONLINEAR ANALYSISES
In this analysis ; Maximum energy absorption value at the point of ultimate elongation strain are observed.
NONLINEAR ANALYSISES
Nonlinear Rubber ( Tensile Test )
Fix
Fix
Force
Displacement [mm]
Forc
e [
N]
Upper Plate
OPERATIONS
OP10 : Blanking Op20 : Forming Op30 : Piercing Op40 : Restrike
Op50: Cam piercing
FORMING SIMULATIONS
COMPARISON
LESS SMALLER , MORE STRONGER DESIGN
PICTURE BELONGS TO 3D PRINT OUT OF NEW DESIGN LOWER CONTROL ARM.
In this study , topology optimization which helps to reduce product costs and to find the optimum design during the product development has been used.
Maximum stresses have been seen on the neck zone which is close to connection points of lower
control arm to cross member during the critical loads . That the material which is low-alloyed and has 700 Mpa yield strength is ideal for lower control arm
and meets the loads enough has been seen.
Consequently , a lower control arm which meets structural durability requirements has been designed , analyzed under linear and nonlinear conditions , and simulated by using forming analysis .
RESULTS & COMMENTS
We applied for a patent on a local hardened and shot-peened lower control arm , with know-how gained after this study.
2013/10157 Lower Control Arm It is about a suspension part.
PATENT APPLICATION
THANKS FOR YOUR ATTENTION
Acknowlegdements : Beltan&Vibracostic R&D Team and Ass.Prof. Mehmet Fırat
CONTACTS : [email protected] [email protected] [email protected] [email protected]