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Lecture on materials selection in equipment design in chemical engineering for undergraduate students - fundamental principles and procedures
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Chapter 2
MATERIALS SELECTION
for EQUIPMENT
ChE514 Chemical Reactor and Process Equipment Design
Chapter 2 Objectives Analyze material performance requirements for a given application
Propose alternative materials of construction for a particular piece of equipment given the performance requirements and application
Screen and rank viable materials candidates
construction for a particular piece of equipment given the performance requirements and application
Chapter 2 Outlinei. Introduction to Materials Selectionii. Materials & Their Attributesiii. The Nature of the Selection Processiv. Analysis of the Material Performance
Requirements & Creating AlternativeSolutions
v. InitialScreening of Solutionsvi. Comparing & Ranking Alternative
Solutionsvii. Selecting the Optimum Solutionviii. Commonly used materialsof construction
in the processindustries
We Already Knew
Classification of Materials According
to the Way Atoms are Bound
Materials
Metals
Semiconductors Ceramics
Polymers
Materials may be Evolutionary
or Revolutionary
Throughout history materials have limited design.
MATERIALS SCIENCE & ENGINEERING
MATERIAL
PROPERTIES
STRUCTURE
Atomic bonding
Crystal structure
Defect structure
Microstructure
Macrostructure
SERVICE
PERFORMANCE
Stresses
Corrosion
Temperatures
Radiation
Vibration
Materials
Science
Materials
Engineering
Performance
cost
Tetrahedron of Materials Science & Engineering Approach
A: CompositionB: Microstructure
C: Synthesis & Processing
Application of the tetrahedron of materials science and engineering to
semiconducting polymers for microelectronics
The Design Process and
Materials Selection
Interrelationship of Factors in Design (M. Ashby)
Goal of Design: To create products that perform their
function economically, safely,at acceptable cost
The (Mechanical) Design Process
Materials Selection is a subset of Mechanical Design.
Mechanical Design
Materials Selection
What is Materials Selection?
General Objective
To select the material which will most
economically fulfill the process and
mechanical requirements .
General Considerations in the Selection
Process
characteristics of the system
characteristics and general behavior of
materials
SELECTION involves seeking the best match between the
property -profile of materials in the kingdom and that
required by the design!
Property-Profile
Asetof materialattributeswhichinclude:
Mechanical, thermal, electrical and chemical
properties
Processingcharacteristics
Costandavailability
Environmentalconsequencesof itsuse
Materials Selection is determined by Function
Function
Process
Shape
Material
Material
Attributes:
Physical,
mechanical,
thermal,
electrical,
environmental,
economic
properties
By its shape
The Role of Materials Selection in Mechanical Design
Design and Materials Selection
Interrelationship among design, materials, and
processing
DESIGN
Service conditions
Function
Cost
PROCESSING
Equipment Selection
Influence on properties
Cost
MATERIALS
Properties
Availability
Cost
Process Environment/Conditions
Temperature Pressure
pH
Presence of trace impurities
Amount of aeration
Stream velocity and agitation
Heat transfer rates
Economics in Materials Selection
True long term cost calculationstotal cost of fabricated equipment and
piping
total installation cost
service life
maintenance costs: amount and timing
time and cost requirements to replace or
repair at the end of service life
cost of downtime to replace and repair
cost of inhibitors, extra control facilities,
etc., required to assure achievement of
predicted service life
time value of money
factors which impact taxation
(depreciation and tax rates)
inflation rate
Materials & Their Attributes