ТА11 А-4 (Ти-811) Титановый сплав

TA11 Titanium Overview

• Type: TA11 (Near-alpha titanium alloy )
• Nominal Composition: Ti-8Al-1Mo-1V
• Stabilizing Elements:
  • Alpha stabilizer: Aluminum (Al)
  • Isomorphous stabilizers: Molybdenum (Mo) and Vanadium (V)
• Характеристики:
  • High elastic modulus
  • Low density
  • Highest specific stiffness among industrial titanium alloys
  • Room temperature tensile strength comparable to TCA alloy
  • Superior high-temperature strength and creep resistance compared to TC4 alloy
  • Higher sensitivity to thermal salt stress corrosion than TC4 alloy
• Приложения:
  • Used in the manufacture of high-pressure compressor disks, лезвия, and casings for aircraft engines
  • Maximum long-term operating temperature: 450°C
  • Commonly produced as bars, forgings, тарелки, полоски, and welding wires
• Плотность: 4.37 г/см³

Material Technical Standards

• XJ/BS 5163—1997: YZTi-811 alloy bars (Baotou Nonferrous Metals Processing Plant)
• AMS 4972D—1990: Solution treated and stabilized Ti-8Al-1Mo-1V alloy bars, провода, and rings

Chemical Composition

Heat Treatment

• Double Annealing:
  • 900-925°C for 1 hour, air cooling
  • 565-595°C for 8 hours, air cooling
• Stress Relief Annealing:
  • 600-700°C for 0.25-4 hours, air cooling or furnace cooling

Melting and Casting Process

• The alloy should undergo at least two vacuum consumable electrode arc melting processes.
• Alloys used for manufacturing aircraft engine rotor parts should undergo three vacuum consumable melting processes.

Application Overview and Special Requirements

• Приложение: Manufacturing of high-pressure compressor rotor blades for aircraft engines
• Special Requirements: Due to the alloy’s sensitivity to chloride stress corrosion, caution is required when used in chloride-containing environments.

Oxidation Resistance

• Comparable to TC4 alloy

Коррозионная стойкость

• Stable in atmospheric conditions and seawater
• Sensitive to chloride stress corrosion at both high temperatures (thermal salt stress corrosion) and ambient temperatures (aqueous stress corrosion)

TA11 Titanium Alloy Microstructure

• Rapid Cooling from Alpha + Beta Phase Region (below 900°C):
  • The beta phase transforms into martensitic structure
• Rapid Cooling below this Temperature Range:
  • Beta phase rich in Mo and V is retained
• Heating at 450°C:
  • Decomposition of beta phase
• Primary Microstructure:
  • Mainly alpha phase with a small amount of beta phase