Corrosion fatigue behavior of coated 4340 steel for blade retention bolts of the AH-1G helicopter. Final report
The main rotor blade bolt for the 540 helicopter rotor system of the AH-1G, UH-1C, and UH-1M helicopters is proposed to be improved by substituting plasma-sprayed tungsten carbide coating on the outer shank of the 4340 steel bolt for the present cadmium or chromium plate. This study was undertaken to determine the effects of these coating systems on the fatigue behavior of 4340 steel in environments likely to be encountered in service. Both axial tension-tension and rotating bending fatigue testing of coated specimens were carried out in air and in 3.5% NaCl solution. The NaCl environment causes reductions in fatigue strength of bare and coated 4340 steel. The severity of the degradation depends on the coating applied and the type of fatigue test utilized.
- Research Organization:
- Army Materials and Mechanics Research Center, Watertown, MA (USA)
- OSTI ID:
- 7223266
- Report Number(s):
- AD-A-033253; AMMRC-TR-76-34
- Country of Publication:
- United States
- Language:
- English
Similar Records
Effects of wear-resistant coatings on the fatigue strength of 4340 steel
Innovations in rotorcraft test technology for the 90's; Proceedings of the AHS National Technical Specialists' Meeting, Scottsdale, AZ, Oct. 8-12, 1990
Related Subjects
360105* -- Metals & Alloys-- Corrosion & Erosion
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
ALKALI METAL COMPOUNDS
ALLOYS
BENDING
CARBIDES
CARBON COMPOUNDS
CHLORIDES
CHLORINE COMPOUNDS
COATINGS
CORROSION FATIGUE
CORROSION PROTECTION
CORROSIVE EFFECTS
DEPOSITION
FATIGUE
HALIDES
HALOGEN COMPOUNDS
IRON ALLOYS
IRON BASE ALLOYS
MECHANICAL PROPERTIES
PROTECTIVE COATINGS
SODIUM CHLORIDES
SODIUM COMPOUNDS
SPRAYED COATINGS
STEELS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN CARBIDES
TUNGSTEN COMPOUNDS