The document outlines the general steps in the materials selection process:
1. Analyze performance requirements and create alternative material solutions.
2. Initially screen solutions based on functional needs, processability, costs, reliability, and resistance to operating conditions.
3. Compare and rank the remaining alternative material solutions.
4. Select the optimal material solution.
2. Introduction
Selecting the appropriate material with
suitable manufacturing process is an
important requisite for the development of
a product.
More than 40,000 metallic alloys and close
to that number of nonmetallic materials.
The selection process a difficult task.
3. Introduction
If the selection process is carried out
randomly, there will be the risk of
overlooking a possible attractive alternative
solution. This risk can be reduced by
adopting a systematic selection.
4. Introduction
The increasing pressure to produce
more economic and competitive products.
New materials and manufacturing
processes.
Makes it necessary for the engineer to be
always on the lookout for possible
improvement.
5. General steps in materials selection
1. Analysis of the performance requirements
and creating alternative solutions
2. Initial screening of solutions
3. Comparing and ranking alternative solutions
4. Selecting the optimum solution
6. General steps in materials selection
Analysis of the performance
requirements and creating alternative
solutions
7. Analysis of material performance
requirements
The material performance requirements can be
divided into five broad categories:
A. • Functional requirements
B. • Processability requirements
C. • Cost
D. • Reliability requirements
E. • Resistance to service conditions
8. A. Functional requirements
Functional requirements are directly related
to the required characteristics of the
component, subassembly, or the product.
Such requirements can generally be
categorized as technical and esthetic.
9. A. Functional requirements
Technical requirements can be related to
physical, mechanical, and chemical
characteristics.
Esthetic characteristics can be related to
color, texture, fashion …, which largely
depend on consumer impressions about
certain materials in a given application.
10. B. Processability requirements
The processability of a material is a measure
of its ability to be worked and shaped into a
finished component.
With reference to a specific manufacturing
method, processability can be defined as
castability, weldability, machinability, etc.
application.
11. C. Cost
Cost is usually a controlling factor in
evaluating materials, because in many
applications there is a cost limit for a given
component.
The cost of processing often exceeds the cost
of the stock material.
In some cases, expensive material may
eventually yield a less expensive product.
12. D. Reliability requirements
Reliability of a material can be defined as the
probability that it will perform the intended
function for the expected life without failure.
Material reliability is difficult to measure,
because it is not only dependent upon the
material’s properties, but it is also greatly
affected by its production and processing
history.
13. E. Resistance to service conditions
The environment in which the product or
component will operate plays an important
role in determining the material performance
requirements.
High or low temperatures, as well as corrosive
environments, can adversely affect the
performance of most materials in service.