Technical guide · 2026-08-14
Alpha-Beta Titanium
Alpha-beta titanium alloys combine alpha stability with beta-enabled processing and heat-treatment response; Ti-6Al-4V dominates, but ELI chemistry, section response and microstructure change fatigue and toughness acceptance.
01
Definition and boundary
Includes duplex-phase titanium systems; Grade 5 and Grade 23 are related but not interchangeable without product specification, interstitial and property review.
Reference information only: final acceptance is controlled by the ordered product specification, condition, dimensions and certified test results.
02
How the material system works
Alpha provides stability while retained/transformed beta aids processing.
Solution treatment and aging alter phase fraction and strength.
Interstitial cleanliness and defects strongly affect fatigue-critical parts.
03
Representative grades and systems
| Grade or system | Selection focus | Qualification |
|---|---|---|
| Ti-6Al-4V Grade 5 | General alpha-beta titanium alloy. | Confirm the governing product specification, delivery condition, section size and acceptance tests before treating designations as interchangeable. |
| Ti-6Al-4V ELI Grade 23 | Lower-interstitial variant for toughness-critical duty. | Confirm the governing product specification, delivery condition, section size and acceptance tests before treating designations as interchangeable. |
| Ti-6Al-6V-2Sn | Higher-strength alpha-beta forging system. | Confirm the governing product specification, delivery condition, section size and acceptance tests before treating designations as interchangeable. |
04
Properties and trade-offs
High specific strength
Heat-treatable strength-toughness balance
Fatigue sensitivity to surface and defects
05
Product forms and supply conditions
06
Applications and selection
Applications and selection
- Airframe forgings
- Aerospace fasteners
- Medical and energy components
Properties and trade-offs
- Do not infer ELI from trade name alone.
- Set microstructure by fatigue, fracture and section need.
- Coordinate machining damage and surface enhancement.
07
Fabrication, durability and inspection
Control beta transus-relative heating.
Prevent white layer and abusive grinding.
Use qualified stress relief after heavy machining.
08
Procurement checklist
- State Grade 5 or 23 and form-specific standard.
- Define melt route, heat treatment and microstructure acceptance.
- Specify ultrasonic class, test orientation and surface integrity.
09
Standards, sources and review
Standards and designation context
- Applicable ASTM B10 titanium product specification
- Buyer drawing and approved material condition
- Qualified inspection and certification plan