Page 479 - Corrosion Engineering Principles and Practice

446 C h a p t e r 1 1 M a t e r i a l s S e l e c t i o n , Te s t i n g , a n d D e s i g n C o n s i d e r a t i o n s 447

11.4.1 Identify Initial Slate of Candidate Materials
The flow chart in Fig. 11.9 illustrates a generic process for screening
materials through a host of traditional means. Designers should
initiate this process by first identifying a slate of candidate materials
possessing the necessary physical, mechanical, thermal, and/or
electrical properties. The number of materials chosen as initial
candidates may vary depending with the criticality of the application
and the design process employed.
The advantage of considering a larger number of materials at the
first stage of a selection process is obviously to increase the likelihood

Identification of candidate materials

Identify past corrosion failure modes in similar applications

Are there Are there
any problematic Yes Eliminate the material any materials No
materials? from the list left?
No
Yes
Conduct environmental assessment
Discount unlikely forms of corrosion
Identify potential corrosion failure modes

Are there Are there
any problematic Yes Eliminate the material any materials No
materials? from the list left?
No
Yes

Is corrosion Yes Select corrosion
protection protection scheme
required?
No
Evaluate availability and maintainability
Are these
Perform cost analysis results No
acceptable?
Yes
Prioritize, rank, and select optimum material and corrosion protection scheme

FIGURE 11.9 Generic process for selecting materials to improve corrosion
resistance—a roadmap to life-cycle cost reduction.