Development of Custom 465® Corrosion-Resisting Steel for Landing Gear Applications

Abstract

Existing high-strength low-alloy steels have been in place on landing gear for many years owing to their superior strength and cost performance. However, there have been major advances in improving the strength of high-performance corrosion-resisting steels. These materials have superior environmental robustness and remove the need for harmful protective coatings such as chromates and cadmium now on the list for removal under REACH legislation. A UK government-funded collaborative project is underway targeting a refined specification Custom 465 Ò precipitation hardened stainless steel to replace the current material on Airbus A320 family aircraft main landing gear, a main fitting component developed by MessierBugatti-Dowty. This is a collaborative project between Airbus, Messier-Bugatti-Dowty, and Carpenter Technology Corporation. An extensive series of coupon tests on four production Heats of the material have been conducted, to obtain a full range of mechanical, fatigue, and corrosion properties. Custom 465 Ò is an excellent replacement to the current material, with comparable tensile strengthand fracture toughness, better ductility, and very good general corrosion and stress corrosion cracking resistance. Fatigue performance is the only significant area of deficit with respect to incumbent materials, fatigue initiation being often related to carbo-titanium-nitride particles and cleavage zones.

Surface Finish Comparison of Dry and Coolant Fluid High-Speed Milling of JIS SDK61 Mould Steel

“…The coolant fluid is essential when milling hardened steel or other difficult-to-machine materials, especially when machining at high speeds. The main effect of a coolant in milling is to reduce temperature and friction, prolong the life of the cutting tool, and improve the machining efficiency and surface quality [1][2][3]. Moreover, a coolant also has anticorrosion and cleaning effects [4,5].…”

Influence of grinding and shot-peening on the near-surface microstructure of a maraging stainless steel

“…Maraging stainless steels offer a promising alternative for replacing conventional high strength martensitic steels for applications requiring high levels of mechanical properties, with a property portfolio comprising high strength, toughness and corrosion resistance [ 1 , 2 ]. However, their fatigue strength, which is an important property for these structural components, is relatively low in comparison with the conventional high strength steels [3] . Shot peening is an effective treatment for improving the fatigue strength of maraging steels [4][5][6][7] .…”

Exploring New Strategies for Ultrahigh Strength Steel via Tailoring the Precipitates

“…ii) Maraging steels: Custom 465 (famous high-strength stainless steel) (Daymond et al, 2016), 18Ni (strongest UHS with acceptable ductility and toughness) (Wang, B. et al, 2017), PH 13-8Mo (well-known high-strength stainless steel) (Leitner et al, 2011);…”