Author
mason-said
View
220
Download
0
Tags:
Embed Size (px)
DESCRIPTION
material processes
1
MATERIALS SELECTION AND
FAILURE ANALYSIS
Materials & process selection to manufacture a product is
tedious task, >80000 materials & >1000 process to choose
from It starts with DESIGN
What is Design?
The process of translating a new idea of a market need into
detailed information from which a product can be
manufactured (Reason = Market need)
Fig. 1: Interrelationship among design, materials, and processing (ASM
Handbook, Volume 20: Materials Selection and Design, G.E. Dieter, editor, p 243-254, DOI: 10.1361/asmhba0002450)
2
Design Process defines a market need and selects concepts
(ideas) to satisfy that need
The concepts are refined to embodiments, i.e. sketch
Detailed design and generation of working drawings
Figure 2
Fig. 2: Schematic of the design process with design tools on the left and
materials and process selection on the right. At the concept stage of design, the
emphasis is on breadth; in the later stages, it is on precision. FEM, finite
element modelling; DFM, design for manufacturing; DFA, design for assembly
(ASM Handbook, Volume 20: Materials Selection and Design, G.E. Dieter, editor, p 243-254, DOI: 10.1361/asmhba0002450)
3
Some of information required
Approximate data required for the top
Precise & detailed data required for
materials & process here
Fig. 3: The design flow-chart. Materials and process information is required at
every step-breadth at the top, detail at the bottom
Fig. 4: Data for materials and processes takes a spectrum of forms, ranging from
numeric data for standard properties (like density) to experience derived from past
applications. One challenge in constructing selection tools is that of making the
maximum use of all forms of data. M.F. Ashby Mats. & Design, 25, 51-67, 2004 (both)
4
Design has Four Principal attributes
1- Function (what does it do)
2- Appearance
3- Manufacturing method
4- Cost
Function:
1- Define it precisely 2- Design synthesis basic idea to do the function, the
constraints
3- Decision making, e.g. dimensions, dimension tolerances, materials, manufacturing process
4- Analysis
Fig. 5
Appearance
If in view, must look attractive as possible, e.g. vacuum
cleaner, car, and should be in harmony with surrounding
Cost:
Initial selection due to properties but final decisions always
involves considerations of cost which in most cases will be
the dominant criterion. The total cost of a manufactured
article in service is made up of several parts, (Figs. 6)
5
Fig 5: Design flowchart, Charles & Crane book(2nd edition, 1989)
6
Fig. 6: Cost analysis, Charles & Crane book (2nd edition, 1989)
Product development: Before marketing or erecting the
new plant, wise to do field trial or pilot plant studies,
overdesign the early batches to get good reputation in the
market, then optimize, Overdesign means over price, but it
is a judgment to be done.
Reduce specification once it has been established as a good
product.
Process of optimization: Evaluating improvement by
feedback from production depts., accountants and users
need ~20% improvement to justify changes in specification
7
MATERIALS AND MANUFACTURING
METHODS AVAILABLE TO ENGINEERS
As part of design are the materials and manufacturing process
selections;
M.F. Ashby Mats. & Design, 25, 51-67, 2004 (both)
Fig7:
8
Fig. 8: Hierarchy of metals available to Engineers (Reza Ghomashchi Book, UniSA 1999)
9
Fig. 9: Hierarchy of ceramics available to Engineers (R.Ghomashchi,1999)
10
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
Fig. 10: Hierarchy of
Polymers available to
Engineers
R. Ghomashchi, 1999
11
Fig. 11: Hierarchy of Composites available to Engineers (R. Ghomashchi, 1999)
Fig.12: Materials chart, M.F. Ashby , Butterworth-Heinemann ,2003
12
Table 1: Several examples of materials applications in a variety of products (R. Ghomashchi, 1999)
13
MANUFACTURING PROCESSES (Techniques)
Fig. 14: Schematic diagram to show the interrelationships amongst
materials processing, microstructure and properties (R. Ghomashchi, 1999)
Fig. 13: Manufacturing processes (R. Ghomashchi, 1999)
14
Fig. 15: Manufacturing processes
Casting (R. Ghomashchi, 1999)
15
Fig. 16: Manufacturing Processes Forming (R.Ghomashchi, 1999)
Fig. 17: Manufacturing Processes Powder processing (R.Ghomashchi, 1999)
16
Fig. 18: Manufacturing Processes Machining (R.Ghomashchi, 1999)
Fig. 19: Manufacturing Processes Joining (R.Ghomashchi, 1999)
17
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
Fig. 20: Manufacturing processes
18
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
19
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
20
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
21
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
22
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
23
L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
24
25
26
27
28
29
30
31
32
33
34
35
Main references used in this section
1- Ashby 2004, M.F. Ashby, Y.J.M. Brechet, D. Cebon, L. Salvo, Selection strategies for materials and processes, Mats. & Design, 25, 51-67, 2004
2- Charles & Crane book(2nd edition, 1989), J.A. Charles, F.A.A Crane, Selection and use of engineering materials, 2nd edition, Butterworths,1989
3- R. Ghomashchi Book, 1999, M.R. Ghomashchi, An introduction to Engineering Materials, University of South Australia, 1999.
4- L. Edwards & M. Endean, (Editors)Manufacturing with Materials, Butterworth-Heinemann,1995, Open University
5- M.F. Ashby, Butterworth-Heinemann ,2003, Materials selection in Mechanical Design, 2
nd edition, 2003
All Slides are from: L. Edwards & M. Endean, Manufacturing with Materials, Butterworth-Heinemann,1995
36
Notes: