Module 5 Non-Ferrous Alloys Objective Four

Question 1

Magnesium Alloys

Answer 1

usually have the highest strength to weight ratio of commercial metals, but are relatively brittle due to HCP structure, with poor corrosion resistance, poor wear creep and fatigue properties

Question 2

Zinc Based alloys

Answer 2

zinc coating in these alloys is usually used as a sacrificial anode, as the zinc will corrode first

Question 3

Alpha Titanium

Answer 3

Titanium alloy has (Al, O, N, or C) which stabilizes the HCP structure, stronger then beta, but more brittle

Question 4

Beta Titanium

Answer 4

titanium alloys that contain alloying elements to stabilize the BCC structure (Mo V lower transformation temp, and Fe, Cr, Mn cause the transformation to be extremely slow) some ductility

Question 5

Alpha-Beta Titanium

Answer 5

have enough stabilizers so they can be worked like Beta, and then heat treated to give controlled decomposition to alpha phase, gives higher strength

Question 6

Monel

Answer 6

67% Ni/30% Cu, the best commercial alloy for corrosion and erosion resistance, useful for resisting metal loss in high velocity or turbulent corrosive environments

Question 7

High Temperature Alloys

Answer 7

use Tungsten Molybdenum, Niobium and Rhenium, as they’re very resistant to heat, wear and corrosion, cannot be casted

Question 8

Superalloys

Answer 8

cobalt and nickel based alloys can operate above 1100 Celsius, difficult to machine