Materials for engineering, 3rd Edition - (Malestrom)

96
Materials for engineering
1400
1 2 3 Wt% Be
1300
1200
L
1100
1038
1000
Temperature (°C)
900
800
700
α
16.4
14.8
12.4
868
600
10.0
605
500
6.6
400
2.75
300
1.35
α + β
200
0 10 20 At% Be
3.14 The Cu-rich end of the Cu–Be phase diagram.
grain boundaries and inhibits the precipitation of coarse particles of CuBe in
those regions. Tensile strengths in the order of 1400 MPa can be achieved,
but with elastic moduli only two-thirds that of steel. This allows a large
deflection for a given stress in such applications as springs, diaphragms and
flexible bellows.
Copper alloys of high solute content
Zinc, aluminium, tin and nickel are the most widely employed alloying
elements in copper, so we will consider the commercial alloys in terms of
these four groups.
The structure of the copper–zinc alloys or brasses can be understood from
the phase diagrams of Fig. 3.15. The zinc content can vary between about 5
and 40%; up to about 35% Zn single-phase α-solid solutions are formed with