Titanium and Titanium Alloys: Strength – to – Weight Ratio & ASTM Grades

Core Advantage

Titanium and its alloys boast a high strength – to – weight ratio — superior to other metals. Unalloyed titanium matches some steels in strength but weighs nearly half as much, making it ideal for weight – sensitive applications (aerospace, automotive, etc.).

ASTM Grade Specifications

The table below outlines key mechanical properties (UTS, YS, Young’s Modulus) and alloy details for titanium grades, aligned with industry standards:

ASTM Grade	Alloy Composition	Min. UTS (MPa)	Min. YS (MPa)	Young’s Modulus (GPa)	UNS No.	Sour Service Approved*
1	Unalloyed Ti	240	170	103	R50250	–
2	Unalloyed Ti	345	275	103	R50400	Yes
3	Unalloyed Ti	450	380	103	R50550	–
4	Unalloyed Ti	550	480	105	R50700	–
5	Ti – 6Al – 4V	895	825	114	R56400	–
6	Ti – 5Al – 2.5Sn	825	795	110	R54250	–
7	Ti – 0.15Pd	345	275	103	R52400	–
9	Ti – 3Al – 2.5V	620	485	107	R56320	–
10	Ti – 11.5Mo – 6Zr – 4.5Sn	690	620	103	R58030	–
11	Ti – 0.15Pd	240	170	103	R52250	–
12	Ti – 0.3Mo – 0.8Ni	485	345	103	R53400	Yes
13	Ti – 0.5Ni – 0.05Ru	280	170	103	R53413	–
14	Ti – 0.5Ni – 0.05Ru	410	280	103	R53414	–
15	Ti – 0.5Ni – 0.05Ru	480	380	103	R53415	–
16	Ti – 0.05Pd	345	275	103	R52402	–
17	Ti – 0.05Pd	240	170	103	R52252	–
18	Ti – 3Al – 2.5V – 0.05Pd	620	480	105	R56322	–
19	Ti – 3Al – 8V – 6Cr – 4Zr – 4Mo (Beta C)	795	760	93 – 96	R58640	Yes
	aged	1170	1105	102	–	–
20	Ti – 3Al – 8V – 6Cr – 4Zr – 4Mo – 0.05Pd	795	760	93 – 96	R58645	–
	aged	1530	1879	165	–	–
21	Ti – 15Mo – 2.7Nb – 3Al – 0.25Si (TIMETAL 21S)	790	760	103	R58210	–
	aged	1170	1100	103	–	–
23	Ti – 6Al – 4V ELI	825	760	114	R56407	–
24	Ti – 6Al – 4V – 0.05Pd	900	830	113	R56405	–
25	Ti – 6Al – 4V – 0.5Ni – 0.05Pd	900	830	113	R56403	Yes
26	Ti – 0.1Ru (Grade 2 interstitials)	345	275	103	R52404	–
27	Ti – 0.1Ru (Grade 1 interstitials)	240	170	103	R52254	–
28	Ti – 3Al – 2.5V – 0.1Ru	620	485	107	R56323	Yes
29	Ti – 6Al – 4V – 0.1Ru	825	760	114	R56404	Yes

Key Applications by Grade

• Grade 2 (Unalloyed Ti): Sour service – approved; used in oil/gas pipelines, chemical processing (corrosion resistance).
• Grade 5 (Ti – 6Al – 4V): High strength – to – weight; aerospace (aircraft frames, engine parts), medical implants.
• Grade 12 (Ti – 0.3Mo – 0.8Ni): Sour service – approved; offshore oil/gas equipment (resists H₂S corrosion).

Material Properties Overview

• Strength: Ranges from 240 MPa (Grade 1) to 1530 MPa (aged Grade 20), suiting low – to – high – stress environments.
• Corrosion Resistance: Alloys with Pd/Ru (e.g., Grade 7, 25) excel in harsh chemical environments.
• Weight Advantage: Density ~4.5 g/cm³ (vs. steel ~7.8 g/cm³), critical for lightweight designs.