300M steel is used extensively for aircraft landing gears because of its high strength, ductility and toughness. However, like other high-strength steels, 300M steel is vulnerable to corrosion fatigue and stress corrosion cracking, which can lead to catastrophic consequences in the landing gear. Stainless steels offer a combination of corrosion, wear, and fatigue properties. But for an aircraft landing gear application a higher surface hardness is required. A laser cladding process with fast heating and cooling rates can improve the surface hardness. AISI 4340 steel is used as a lower cost alternative to 300M due to its similar composition. In this study, the influence of laser cladding process parameters, shield gas, and composition of the deposition and dilution zone has been investigated. The microstructures and composition analysis were evaluated by Scanning Electron Microscopy (SEM) and Optical Microscopy. The deposition hardness varies from 330HV to 600HV.

Meeting Name

20th Annual International Solid Freeform Fabrication Symposium (2009: Aug. 3-5, Austin, TX)


Mechanical and Aerospace Engineering

Second Department

Materials Science and Engineering

Research Center/Lab(s)

Intelligent Systems Center


This research was supported by the National Science Foundation Grant Number DMI-9871185, the grant from the U.S. Air Force Research Laboratory contract # FA8650-04-C-5704, and Missouri S&T Intelligent Systems Center. Their support is greatly appreciated.

Keywords and Phrases

Deposition; Landing Gear (aircraft); Scanning Electron Microscopy; Stress Corrosion Cracking; Aircraft Landing Gear Applications; Catastrophic Consequences; Composition Analysis; Direct Diode Laser; Fatigue Properties; Heating and Cooling Rates; Laser-Cladding Process; Stainless Steel 316L; Stainless Steel

Document Type

Article - Conference proceedings

Document Version

Final Version

File Type




Publication Date

05 Aug 2009