Archives du mot-clef fasteners

Failure analysis of titanium alloy fasteners for aerospace applications

Publié le par
Répondre

2016-11-16_18h46_14A paper published in « Case Studies in Engineering Failure Analysis« , available on sciencedirect.com.

As a qualification of bolt for flight assembly, the bolt assembly has undergone proof pressure test at 2.4 MPa, Vibration test at frequency range of 20–100 Hz, ±3 db/oct for 120 s in both lateral and longitudinal directions and flight acceptance test. During routine visual inspection before electrical check, it was observed in one of the three fasteners that the head of the bolt had got sheared off from the shank portion of bolt. Further, a failure analysis was carried out on the failed bolt.

The objective of the study is metallurgical analysis of the failed bolt, fractography study to find out the root cause of the failure, and optimization of processing parameters for fastener manufacturing.

Read more ….

Shape Fastener of the Bus Skeleton Testing

Publié le par
Répondre

fasternerA paper presented at « International Conference on Electromechanical Control Technology and Transportation » (ICECTT 2015).

The paper deals with the bending tests of new designed joints for bus skeletons. The frames of buses have to satisfy various demands, but the safety of the passengers is the priority. The actual welded joints should be replaced by new type of profiles connections in the future. Finite elements method was used for the bending test simulation and for the stress investigation; the real experiments were done using the universal test equipment ZD10/90. Obtained results are comparable, so authors aim to realize next experiments in next days at which other shapes of the joints will be tested. Read more

Use of Aerospace Fasteners in Mechanical and Structural Applications

Publié le par
Répondre

Hugh Magma lockUn article paru dans «  Annals of Materials Science & Engineering« , publié sur www.austinpublishinggroup.com

Abstract. The intention of the present short review is to introduce to the non-specialist reader the feasibility of the use of alternative materials not generally considered by engineers working in mechanical and structural applications. That is, the use of specialised aerospace rivets in the more general area of construction is considered. To this end, the text briefly overviews the different types of fasteners used in the construction industry and their common mechanisms of failure.

Une proportion importante des défaillances mécaniques sont liées à des problèmes d’assemblage. Vissage, soudage, rivetage, collage… aucun type n’est épargné.

Le Cetim traite pour sa part, plus d’une centaine de cas d’analyses de défaillance liés à cette problématique par an.

Erreurs de conception, problèmes de procédés ou de mise en œuvre d’assemblage, défauts de matière, sont autant de pistes à explorer pour identifier et localiser les origines du problème. Des solutions correctives et pérennes appropriées sont ensuite proposées et mises en œuvre. Les experts du Cetim se tiennent à votre disposition pour vous apporter conseils et expertises dans cette problématique. N’hésitez pas à les contacter : cliquez ici.

 

Hydrogen embrittlement in steel fasteners

Publié le par
Répondre

hydrogen embrittlementThis paper is published on http://www.boltcouncil.org by Salim Brahimi, President at IBECA Technologies Corp, Chairman, Committee F16 (Fasteners) at ASTM International, The objective of this paper is to distil the latest knowledge related to hydrogen embrittlement into know-how in a manner that is complete yet simple, and directly applicable to fasteners. The topic is divided into basic components. First is a description of the theory and mechanism of hydrogen damage, followed by a discussion of conditions that are necessary for hydrogen embrittlement failure to occur. The fundamentals are followed by a description of HE test methods, guidelines for processing, surface cleaning, coating (particularly electroplating), and baking.

telecharger le doc