TITANIUM AND ALLOYS — MIND MAP

TITANIUM AND ALLOYS — MIND MAP

1. Classification of Titanium Alloys

   • Commercially Pure Titanium (CP Grades 1–4)
     • - High ductility, low mechanical strength, low impurities
     • - Very high corrosion resistance
   • Alpha Alloys (α)
     • - Non–heat-treatable
     • - Excellent weldability and creep resistance
     • Examples: Ti-5Al-2.5Sn
   • Beta Alloys (β)
     • - Heat-treatable, highest strength levels
     • - Good formability in solution-treated state
     • Examples: Ti-10V-2Fe-3Al
   • Alpha-Beta Alloys (α-β)
     • - Balanced strength, toughness, fatigue and corrosion resistance
     • - Most widely used group
     • Example principal: Ti-6Al-4V (Ti64)

2. Main Characteristics & Properties

   • General Titanium Properties
     • High strength-to-weight ratio
     • Low density: ~4.5 g/cm³
     • Very high corrosion resistance: seawater, chlorides, oxidizing environments
     • Excellent fatigue resistance
     • Non-magnetic & biocompatible
   • Pure Titanium (CP Grades 1–4)
     • Outstanding corrosion resistance
     • High ductility, low strength compared to alloys
     • Used where formability & corrosion are key
     • Poor high-temperature strength
   • α Alloys
     • Maintain properties at high temperature
     • Excellent creep resistance → suitable for >400 °C
     • Good weldability
     • Lower strength compared to β or α-β alloys
     • Excellent for aerospace hot-section components
   • α-β Alloys (e.g., Ti-6Al-4V)
     • Most used due to balance of strength, toughness, fatigue, and corrosion resistance
     • Heat treatable
     • Moderate-to-good weldability
     • Used for structural aerospace, biomedical implants, military, motorsport
   • β Alloys
     • Highest strength among titanium alloys
     • Great cold-formability in solution-treated state
     • More expensive due to alloying
     • Lower creep resistance than α alloys
     • Ideal for high-strength fasteners & landing gear

3. Applications & Examples

   • Aerospace
     • Airframe components: bulkheads, frames, skins
     • Jet engine parts: compressor blades, discs
     • Landing gear: β-alloy components
     • Reason: high strength, corrosion resistance, temperature capability
   • Biomedical
     • Implants: hip stems, knee components, dental implants
     • Reason: biocompatibility, osseointegration, corrosion resistance
   • Chemical & Industrial
     • Heat exchangers, reactor vessels, chlorine environments
     • Reason: resistance against chlorides & oxidizing media
     • Marine applications: propeller shafts, offshore equipment
   • Energy
     • Turbine blades, offshore platforms
     • Reason: combined strength + corrosion resistance
   • Automotive & Motorsport
     • Connecting rods, springs, exhaust systems, valves
     • Reason: lightweight + high performance
     • Mainly α-β or β alloys
   • Sports
     • Golf clubs, bicycle frames, tennis racquets
     • Reason: strength-to-weight + vibration damping

4. Processing Techniques

   • Primary Processing
     • Melting methods: Vacuum Arc Remelting (VAR), Electron Beam Melting (EBM)
     • Casting: precision casting for complex shapes
     • Powder metallurgy: HIP (Hot Isostatic Pressing), additive manufacturing powders
   • Forming
     • Forging: α-β forgings for aerospace structures
     • Rolling: plate, sheet, bar
     • Extrusion
   • Heat Treatments
     • Solution treatment + aging (mainly for β and α-β alloys)
     • Annealing to improve ductility and relieve stresses
     • Beta annealing for specific microstructure refinement
   • Advanced Manufacturing
     • Additive manufacturing (AM):
     • Surface treatments: anodizing, nitriding, shot peening
       • SLM (Selective Laser Melting)
       • EBM (Electron Beam Melting)
       • Excellent for lattices, implants, aerospace brackets