Titanium Alloys

Question 1

What type of structure does an alpha stabilised Ti alloy have ?

Answer 1

HCP (room temp)

Question 2

What is titanium that is unalloyed or with alpha stabilisers called?

Answer 2

Alpha alloys

Question 3

What are the elements used commonly in alpha alloys?

Answer 3

Aluminium, gallium, germanium and tin

Al, Ga, Ge, Sn

Question 4

What is the most used element in alpha alloys?

Answer 4

Aluminium because it increases the transformation temperature

Question 5

Characteristics of alpha alloys?

Answer 5

-non heat treatable
-good notch toughness
-medium strength
-good creep resistance at high temps

Question 6

Most common elements used in Beta titanium alloys?

Answer 6

Vanadium and molybdenum
Va & Mo

Question 7

What do large amounts of alloying in alpha alloys result in?

Answer 7

Solid solution strengthening

Question 8

What does solid solution strengthening do?

Answer 8

The solute alloying element moves into empty parts of the lattice structure and makes it hard for dislocations to move.

Question 9

In an alpha + beta alloy what does the alpha part do?

Answer 9

The alpha phase acts as a hardener due to solid solution strengthening through the addition of aluminium

Question 10

In an alpha + beta alloy what does the beta part do?

Answer 10

The beta phase stabilises the ductility through the addition of vanadium which alloys hot working of the material

Question 11

Characteristics of alpha + beta Ti alloys?

Answer 11

-high tensile and fatigue strength
-low ductility
-good form ability
-creep resistance up to 425 degrees