Wear surface damage of a Stainless Steel EN 3358 aeronautical component subjected to sliding
Journal Title: Frattura ed Integrità Strutturale - Year 2013, Vol 7, Issue 23
Abstract
The present paper describes the failure analysis of an aircraft component subjected to several episodes of in service failure, resulted in loss of the aircraft safety. Modern aircrafts are provided with mechanical systems which have the task to open not pressurized hatches during landing. The components of such systems are subject to considerable mechanical stresses in harsh environment (presence of moisture and pollutants, significant and sudden temperature variations). The system is constituted by a sliding piston, a related nipple and by a locking system consisting of 4 steel spheres which are forced into a countersink machined on the piston when the hatches is open. The whole system is activated by a preloaded spring. The machined parts, nipple and piston, are made of EN3358 steel (X3CrNiMo13-8-2), a precipitation hardening stainless steel with very low content of carbon often used in the aerospace. The samples provided by the manufacturer present different types of damage all referable to phenomena relative to the sliding of the piston inside the nipple. The present paper describes the different damage observed and the microstructure of the material, then are reported the results obtained from the characterization of the material of the samples by means of optical and electronic microscopy, carried out to define the mechanisms involved in the system seizure. In order to define the primary cause of failure and to propose solutions to be adopted, also analyzing the criticality of using this PH stainless steel for this application, the results of different tests were compared with system design and working data.
Authors and Affiliations
Ferdinando Felli, Andrea Brotzu, Cristian Vendittozzi, Antonio Paolozzi, Francesco Passeggio
Keywords
Related Articles
- EP ID EP161442
- DOI 10.3221/IGF-ESIS.23.13
- Views 59
- Downloads 0
Numerical simulation of dynamic brittle fracture of pipeline steel subjected to DWTT using XFEM-based cohesive segment technique
In the past several numerical studies have addressed the ductile mode of fracture propagation. However, the brittle mode of pipeline failure has not received as much attention yet. The main objective of this ...
Sub-critical cohesive crack propagation with hydro-mechanical coupling and friction
Looking at the long-time behaviour of a dam, it is necessary to assume that the water can penetrate a possible crack washing away some components of the concrete. This type of corrosion reduces the tensile st...
Modelling of ultrasonic impact treatment (UIT) of welded joints and its effect on fatigue strength
Ultrasonic impact treatment (UIT) is a remarkable post-weld technique applying mechanical impacts in combination with ultrasound into the welded joints. In the present work, a 3D simulation method including w...
Mechanical behaviour and durability of high volume fly ash cementitious composites
The purpose of this research is to separate different morphological particles of ASTM class F fly ash, and study their effect on mechanical behaviour and durability of high volume cementitious mixtures. In this res...
A review of using thermoelasticity for structural integrity assessment
The advances in the use of thermoelastic stress analysis (TSA) for fracture mechanics assessment are reviewed. The development of techniques to determine stress intensity factor is presented followed by the applica...