Chapter 3
The Physics of Failure
“Happy is he who has been able to learn the cause of things.”
Virgil (70–19 BC)
3.1 Overview
This chapter examines a scientifically based preferred alternative to the statistical theory of ‘failure inevitability’ that has spawned punitive cost-of-ownership procurement contracts for over half a century. Understanding the causes of failure in materials and components is essential to the task of achieving the prevention of failure occurrence and recurrence. Failure-analysis methods are summarised with the inclusion of references to sources of detailed procedures.
Emphasis is placed upon the penalties incurred by neglecting the essential process of root-cause analysis of failures as an expedient to project milestone achievement. The threat to project success, caused by replacing components suspected of failure from host PBAs, in the interest of achieving rapid repair turn-round, is discussed in order to encourage a deeper understanding of some of the basic principles of failure prevention. An understanding of the most appropriate level of equipment assembly at which to carry out failure analysis is vital to a cost-effective root-cause analysis process. A number of illustrations of device failures, with accompanying narratives, are included in this chapter.
A section of this chapter is devoted to simplifying the processes involved in the transition from tin-lead to lead-free soldering. The physical properties of lead-free solder are summarised as a ...
