Lesson 3
2014
Lesson 3
2014
 Our goal is, that after this lesson, students
are able to implement the systematic
material selection process by collecting the
product’s requirement list and by finding he
corresponding material properties to finally
select the optimized constructional material
of the product.
The importance of proper material
selection is increasing, because:
 New, better materials are and will be available
year after year
 Material properties and materials’ quality are
improving all the time
 The demands of better cost-effectiveness in
engineering requires optimized material
selection
 Environmental aspects and green technology
has become more important in material
selection
 Etc.
DEVELOPMENT PHASES OF MATERIAL TECHNOLOGY
1750
1800
1850
1900
1950
2000
DECADE
DEVELOPMENT OF
CEMENT
DEVELOPMENT OF
THE DIFFERENT
FORMS OF SILICON
DEVELOPMENT OF STEELS
DEVELOPMENT OF
POLYMERS
DEVELOPMENT
OF CARBON
FIBRES
DEVELOPMENT OF
CARBON NANOTUBES
DEVELOPMENT OF
GRAPHENES
NOT ONLY THE MATERIAL ITSELF…
…BUT ALSO ITS APPLICATIONS!
NOT ONLY THE OPTIONAL MATERIALS
OF A SINGLE COMPONENT…
…BUT ALSO THE CRITICAL MATERIAL
PAIRS IN THE CONSTRUCTION
Gas turbine application
NOT ONLY THE OPTIONAL MATERIAL
OF A SINGLE COMPONENT
…BUT ALSO THE OPTIMIZED
MATERIALS IN THE CONSTRUCTION
SHAPED OBJECTS
MADE OF DIFFERENT
MATERIALS
TYPICAL AND EASY
GEOMETRIES AND SHAPES
FOR EACH MATERIAL
GROUP
PRODUCT’S
MATERIAL
SELECTION
PROTOTYPES/
PROTOTYPE
TESTING
CONSTRUCTIONAL
MATERIAL SELECTION
CONSTRUCTION
TECHNICAL
SPESIFICATIONS
PRODUCTION TRIALS
MATERIAL SELECTION PHASES
USER FRIENDLY
GEOMETRY
3D-MODELING
OF THE
PRODUCT
ESTHETIC
VALUES OF
THE SHAPE
“VISION”
PRODUCT AND
PRODUCTION
DEVELOPMENT
COMMERCIALIZED
PRODUCTS
“PROTOTYPE”
“IN REAL USE”
MATERIAL SELECTION CRITERIA
HUMIDITY ABSORPTION
WEAR
LOAD BEARING CAPACITY
STIFFNESS AND RIGIDITY
AGEING
WEAR RESISTANCE
CORROSION
ENERGY ABSORPTION
TEMPERATURE
MATERIAL SELECTION
RAW MATERIAL COSTS
PRODUCTION COSTS
WELDABILITY
SERVICE AND
CASTABILITY
MAINTENANCE COSTS
MACHINABILITY
QUALITY COSTS
FORMABILITY
RECYCLING AND REUSE COSTS
COATABILITY
DISPOSAL COSTS
LCC/LCA
MATERIAL SELECTION IS A COMPROMISE
MANUFACTURING
PRODUCTION
TECHNOLOGIES
MATERIAL
SELECTION
DIMENSIONS AND
GEOMETRY OF
THE PRODUCT
OVERLAPPING AREA FOR
FINDING COMPROMISES
TO ENABLE REASONABLE
MATERIAL SELECTION
SEQUENTAL AND CONCURRENT ENGINEERING
DESIGN
PRODUCT’S
PERFORMANCE
MATERIAL
SELECTION
PRODUCTION
RAPID
PROTOTYPING
MODELING
DESIGN
MATERIAL
SELECTION
(DATABASES)
PRODUCTION
SYSTEMATIC MATERIAL SELECTION PROCESS
FUNCTIONS
CONDITIONS
PRODUCTION
COSTS
FINAL
SELECTION
1. ELABORATION OF THE
REQUIREMENTS PROFILE
LIMITS DUE TO LOAD BEARING CAPACITY
FUNCTIONAL LIMITS
FAILURE MATRIX
ANALYSIS OF THE SUB-ASSEMBLIES
2. DECISION ABOUT THE
SELECTION STRATEGY
ECO-EFFICIENCY
CLEAN AND GREEN TECHNOLOGY
COST-EFFECTIVENESS
RELIABILITY BASED DESIGN
3. PRE-SELECTION OF
POSSIBLE MATERIALS
TYPICAL AND COMMON SOLUTIONS
STANDARDIZED SOLUTIONS
AVAILABLE BULK SIZES AND ALLOYS
4. ELABORATION OF THE
MATERIALS’ PROPERTY
PROFILE
CONCRETE NUMERICAL DATA
MATERIALS’ PROPERTY MAPS
FUNCTION INDEX
FOUR- AND MULTIFIELD ANALYSES
NEW OPTIONS BASED ON HEAT
TREATMENTS AND SURFACE COATINGS
5. INTEGRATION OF THE
REQUIREMENT AND THE
PROPERTY PROFILES
VALUE ANALYSIS
COSTS COMPARISONS
LCA /LCC
6. MONITORING AND
FEEDBACK
 FUNCTIONAL
 CORRESPONDING
REQUIREMENTS
 FUNCTION:
Should remain rigid and stiff
 Enough load bearing capacity is
required against pulsating loading
under varying temperature

 ENVIRONMENTAL CONDITIONS:

Good adhesive and abrasive load
bearing capacity is required
 MANUFACTURING AND
PRODUCTION

Should be cost-effective in mass
production
 COSTS

Eco-efficiency throughout the lifetime is
required
MATERIAL PROPERTIES
 FUNCTION:
Hardness, modulus of elasticity, thermal
coefficient, shear modulus
 Fatigue strength, thermal strength

 ENVIRONMENTAL CONDITIONS:

Hardness, friction co-efficient
 MANUFACTURING AND PRODUCTION

Melting temperature, shrinking rate, wall
thickness
 COSTS

Recycling rate, MI- and MIPS-values
Objective numerical values are
needed for optional materials.
SPUR GEAR 1
SPUR GEAR 2
M
A
T
E
R
I
A
L
P
A
I
R
F
A
T
I
G
U
E
W
E
A
R
ROOT
STRENGTH
REQUIREMENT
MAIN MATERIAL
PROPERTY
Dynamic load bearing
capacity
FATIGUE STRENGTH
SURFACE PROPERTIES
CRACK SENSITIVITY
Torque transmission
capacity
STIFFNESS
BENDING STRENGTH
AND DUCTILITY
DUCTILE CORE AND
HARD SURFACE
REQUIREMENT
MAIN MATERIAL
PROPERTY
Adhesive wear resistance
LOW FRICTION
COEFFICIENT BETWEEN
GEARS
Abrasive wear resistance
HARDNESS DIFFERENCE
BETWEEN GEARS
FORMABILITY
SURFACE PROPERTIES
Fatigue wear resistance
FATIGUE STRENGTH
SURFACE PROPERTIES
Tribochemical wear
resistance
CHEMICAL RESISTANCE
Local surface
compression load bearing
capacity
MODULUS OF ELASTICITY
AND POISSON’S
COEFFICIENT
SURFACE
PRESSURE
P
A
I
R
POWER
TRANSMISSION
CAPACITY BASED
ON THE ALLOWED
SURFACE
PRESSURE ON THE
TOOTH CONTACT
AREA ”WEAR”
REQUIREMENTS
MAIN MATERIAL PROPERTIES
MAIN MATERIAL PROPERTIES
SPUR GEAR 2
OTHER
REQUIREMENTS
BASED ON THE
”FUNCTIONAL
CONDITIONS”
REQUIREMENTS
SPUR GEAR 1
M
A
T
E
R
I
A
L
POWER
TRANSMISSION
CAPACITY BASED
ON THE ALLOWED
BENDING STRESS
AT THE TOOTH
ROOT
”FATIGUE”
Specified properties of
steel alloys
Specified properties of
ceramics
Specified properties of
composites
Specified properties of
HP-polymers
Specified properties of
different steel alloys
Specified properties of
ceramics
Specified properties of
composites
Specified properties of
HP-polymers
RECOGNITION OF THE MAIN SELECTION CRITERION

Is there the risk of too low load bearing capacity?
Dimensioning criteria
Functional limits
Load bearing
capacity
Stability
Plastic
durability
No initial
cracks
Plastic deformation due
to reversed loading
Fatigue failure
Possible
initial
cracks
Brittle fracture
Corrosion
fatigue

Is there the risk that functional limits will be exceeded,
though there is no risk of exceeding the load bearing
capacity?
Dimensioning criteria
Functional limits
Load bearing
capacity
Bending
Local
deformation
E.g. too extensive bending,
local deformations of
vibrations might prevent the
use of the constructions
though no failure wont take
place.
Input (in pulse) x (t)
Output
(response) u (t)
Vibration
Time t
ULTIMATE TENSILE STRENGTH
FOUR-FIELD
ANALYSIS
MIN.
OPERATING
TEMPERATURE
MAX. OPERATING
TEMPERATURE
IMPACT STRENGTH
COBWEBANALYSIS
MODULUS OF ELASTICITY
1/DENSITY
FATIGUE STRENGTH
YELD STRENGTH
HARDNESS
IMPACT STRENGTH
TWO TYPES OF FAILURE MODE MATRIXES
1
2
Component: Ball bearing
Component material:
100Cr5
Part
Failure mode
Failure mode
Outer ring
Abrasive wear
Deformation
Material
property
Abrasive wear
Hardness
Inner ring
Abrasive wear
Deformation
Cage
Corrosion
Yeld strength
Compression
strength
Balls
Abrasive wear
Corrosion
Chemical
corrosion
reistance
MATERIAL SELECTION CUBIC
INTENDED
CORRECTION
FLEXIBLE JOINT
SUPPORT
FORCE TRANSMISSION
OTHER FUNCTION
OTHER ACTION
CHANGE OF MATERIAL
CHANGE OF COMPONENT
DEFELOPMENT OF THE COMPONENT
WEAR
DUCTILE FRACTURE
OTHER FAILURE
FATIGUE FAILURE
BRITTLE FRACTURE
FAILURE MODE OF
THE COMPONENT
THE CELL, WHICH DESCRIBES THE MEANING
OF MATERIAL CHANGE WHEN THE PURPOSE IS
TO AVOID FATIGUE FAILURE IN A FORCE
TRANSMISSION COMPONENT
MAIN FUNCTION
OF THE
COMPONENT
SPECIAL FEATURES IN SELECTING CONSTRUCTIONAL MATERIALS
SELECTION CRITERIA BASED
ON CORROSION RESISTANCE
GREEN
TECHNOLOGY
SPECIAL FEATURES
IN SELECTING
CONSTRUCTIONAL
MATERIALS
SYSTEMATIC
SELECTION
PROCESS
WEB-BASED TOOLS FOR MATERIAL SELECTION

http://www.format.mwn.de/Werkstoffe/statisch/werkstoffsuche/werkstoffsuche_de.jsp
CONCLUSIONS…
 Typically the material database includes only a list of material’s




properties
To be able to fully utilize material databases the detailed requirements’
profile is needed to find the necessary numerical values for specific
material properties
Usually the user should have enough knowledge and experience to be
able to make compromises between different material properties and to
make the final selection of the material
There might be some ”subjectivity” in commercial databases
Databases made for specific application areas give some suggestions
of materials and their cost and lifetime data, but usually quite strict
limitations are given to the ”results” validity.
“The
DeZURIK Elastomer, Polymer and Metal Selection Guide is designed to be
used as a guide in selecting the most cost effective valve material. It should only
be used as a starting point. There are a variety of conditions which can affect
the material chosen. Careful consideration must be given to temperature, the
presence of other materials in the solution and the concentration of the media
before the material can be selected.”
Remember the content of our
repetititon lectures…
 What type of strength is needed?
 Strength in elevated temperature, in corrosive environments…
 Varying loads: pulsating, reversed…
 Compression, tensile, bending, share…
 What type of corrosion is affecting?
 Erosion, pitting, galvanic corrosion etc.
 The only solution is NOT “stainless steels “
 There are different types of stainless steels available
 What type of wear is affecting?
 Abrasive, adhesive, tribochemical or fatigue wear?
 The only solution is NOT to find harder materials