Выражение встречается в следующем контексте:

In order to assist workover forecasting in this field workover rig project, the company requested to provide Mean Time To Failure (MTTF) estimates of the mechanical completion components in a conventional cased and perforated completion. All interventions due to reservoir events were excluded for this analysis. In addition, it was requested that the top three failed components for each metallurgy type (CRA, CRA/C90 and C90) be identified.

имеется ввиду сплав металла?

Заранее спасибо