Navy product-improvement program for Turbomach T-62t APU's corrosion-resistant turbine wheel/improved bearing and lubrication system. Final report, 19 January 1983-12 April 1986

Technical Report · Mon May 12 00:00:00 EDT 1986

OSTI ID:6423691

Robertson, W A

Titan T-27 and T-40-1 gas turbine engines have used IN-713 LC turbine wheels for many years without serious hot-corrosion problems. For extended operation in marine environments, however, the well-known susceptibility of Alloy 713 to hot corrosion (sulfidation) could lead to deterioration of airfoil surfaces resulting eventually in loss of engine performance, or even engine failure. Corrosion protection could be enhanced by protective coatings; however, with base material so poor in hot-corrosion resistance as Alloy 713, the reliability of a 713 turbine wheel would be suspect. Also, degradation of mechanical properties accompanying the coating process would reduce the safety margin below acceptable, and appears to justifya material change to an alloy with better hot-corrosion resistance. The alloy selected was MAR-M247, a nickel-based alloy with 10% cobalt, 10% tungsten, 8,25% chromium, 5.5% aluminum, 3% tantalum, 1.5% hafnium, 1% titanium, and other elements. The expected improvements over IN-713 LC include improved oxidation/hot corrosion resistance, blade creep resistance, and tensile strength.

• Research Organization: Sundstrand Turbomach, San Diego, CA (USA)
• OSTI ID: 6423691
• Report Number(s): AD-A-178084/0/XAB; ERR-0632
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
33 ADVANCED PROPULSION SYSTEMS
AIRFOILS
CORROSION RESISTANT ALLOYS
ALLOY-MAR-M246
CORROSION RESISTANCE
MECHANICAL PROPERTIES
PROTECTIVE COATINGS
GAS TURBINE ENGINES
NICKEL ALLOYS
CHROMIUM
COBALT
HIGH TEMPERATURE
LOSSES
LUBRICATION
OPERATION
RELIABILITY
SAFETY
TANTALUM
TITANIUM
TUNGSTEN
ALLOYS
ALUMINIUM ALLOYS
CHROMIUM ALLOYS
COATINGS
COBALT ALLOYS
ELEMENTS
ENGINES
HEAT ENGINES
INTERNAL COMBUSTION ENGINES
METALS
MOLYBDENUM ALLOYS
NICKEL BASE ALLOYS
TANTALUM ALLOYS
TITANIUM ALLOYS
TRANSITION ELEMENTS
TUNGSTEN ALLOYS
360105* - Metals & Alloys- Corrosion & Erosion
330103 - Internal Combustion Engines- Turbine