Purpose -The purpose of this paper is to investigate the effect of fatigue life reduction of 2024 Al alloy for aerospace components due to the corrosive (exfoliation) environment. Both standard fatigue tests on prior corroded samples and fatigue tests conducted with the samples in corrosive solution are developed to define some guidelines for the inclusion of such effect in design and to improve aircraft life management. Design/methodology/approach -The effect of corrosion is taken into consideration, introducing specific concentration factors into the life estimation relationship. Differences between fatigue in corroded specimens and fatigue in presence of corrosive environment are emphasized. No crack propagation is considered. Two alternative procedures are considered in the analysis: "a-procedure" based on maximum stress calculated on un-corroded sample section; "b-procedure" based on stress calculated on final residual section, including corrosion. Findings -Related concentration factors are derived and compared by the experimental results with the aid of an original proposed a "power law". Typical power law (square kt) has been derived to cope with the coupling effect of fatigue and corrosive environment. Research limitations/implications -The original approach developed in the paper is based on few samples. For this reason, the conclusions are addressed as tendency behaviour. Practical implications -The combined effect of fatigue load acting in presence of corrosive environment reveals an important reduction in fatigue life that cannot be determined by means of classical fatigue tests performed on prior corroded samples. Social implications -Specific design updating procedure can be determined to cope with ageing of structures during service improving structural integrity. Originality/value -The derivation indicates a substantial equivalence of the considered two procedures both in the case of prior corroded samples and in combined situation. This tendency is consistent with the available data results. Original analytical relations are introduced to manage such kind of combined effect revealing consistency of data also if few samples were tested.

Starting with its definition, the principles of quality assurance (QA) are described, along with its general characteristics in the field of composite materials. The QA program is not standard and depends on the frame where it has been developed. From the craftsman/artisan organization, essentially based on handworkers, to the formal complex organization, in which a strong staff is mandatory, the QA program changes considerably. International standards, such as International Organization for Standardization (ISO) or AS/EN, and regulations help to develop the right program, indicating the content of documentation to be developed. Suggestions about the general characteristics of quality manual and procedures and consequent “system monitoring” are furnished, in order to also get international certifications. Guidelines to develop an exhaustive quality control (QC) program are furnished, highlighting the main characteristics, along with standards that may be taken as reference. The different phases of the product manufacturing are described, reporting how the QC program should be tailored for each of them. The analysis of basic raw materials for composites is performed, highlighting how the QC program should change, passing from solid to liquid raw materials or as a consequence of their different manufacturer. A similar analysis is performed for preimpregnated materials (prepregs). Finally, a description of the statistical process control methodology is reported, highlighting its advantages but also its limitations.