Wieland-K55®
Rolled Products
CuNi3Si1Mg
C70250
Material Designation
Chemical Composition (Reference)
Typical Applications
EN
no EN standard
Ni
3%
UNS*
C70250
Si
0.65 %
Mg
0.15 %
Cu
balance
· Components for the electrical industry
· Stamped parts
·Connectors
· Relay springs
· Semiconductor components
* Unified Numbering System (USA)
Physical Properties*
Electrical
Conductivity
MS/m
%IACS
25
43
Thermal Conductivity W/(m·K)
190
Coefficient
of Electrical
Resistance**
10-3/K
1.8
Coefficient of
Thermal Expansion** 10-6/K
17.6
Density
8.82
g/cm3
Modulus of Elasticity GPa
Specific Heat
130
0.399
J/(g·K)
Poisson’s Ratio
0.34
* Reference values at room temperature
** Between 0 and 300 °C
Fabrication Properties
Corrosion Resistance
Capacity for Being
Cold Worked
good
Machinability
less suitable
Capacity for Being
Electroplated
Wieland-K55® has good corrosion
resistance in natural atmosphere. It is
insensitive to stress corrosion
cracking.
good
Capacity for Being
Hot-Dip Tinned
good
Soft Soldering
good
Resistance
Welding
fair
Gas Shielded
Arc Welding
good
Laser Welding
less suitable
K55
Mechanical Properties
R690
R760
TR02
Tensile Strength Rm
MPa
620–760
620–740 34 650–780
690–800
760–840
608–725
Yield Strength Rp0.2
MPa
≥ 500
≥ 550
Elongation A50mm
%
≥ 10
≥ 14
(180–220)
(180–230)25 (200–240)
Hardness HV (for information only)
R620
Y550
37
El. Conductivity (MS/m)
Temper
R650
31
≥ 585
≥ 655
≥ 720
550–650
28
≥7
≥5
≥7
≥6
(220–260)
(210–250)
(180–220)
22
19
R620
Y550
R650
R690
R760
TR02
Temper
37
6
34
5
31
28
25
22
19
R620
Y550
R650
R690
Temper
K55
6
90°
Bendability (Strip Thickness t ≤ 0.5 K55
mm)
K55
R760
TR02
Rel. Bending Radius r/t
El. Conductivity (MS/m)
Electrical Conductivity
4
3
180°
bending edge –I rolling direction
bending edge II rolling direction
2
1
0
R620
Y550
R650
R690
Temper
R760
TR02
Wieland-K55®
CuNi3Si1Mg
C70250
K55
220
220
210
210
200
200
190
190
180
170
160
Temper R620
400 °C
450 °C
500 °C
150
140
130
0
5
10
15
20
Time (min)
25
30
Vickers Hardness HV
Vickers Hardness HV
Resistance
K55to Softening
Vickers hardness
after heat treatment
(typical values)
180
170
160
Temper TR02
400 °C
450 °C
140
500 °C
130
0
5
10
15
20
Time (min)
150
25
30
K55
Thermal Stress Relaxation
Stress remaining after thermal relaxation as a function of Larson-Miller
parameter (F. R. Larson, J. Miller, Trans
ASME74 (1952) 765–775) given by:
P = (20 + log(t))*(T + 273)*0.001.
Time t in hours, temperature T in °C.
Example: P = 9 is equivalent to
1.000 h/118 °C.
Measured on stress relief annealed
specimens parallel to rolling direction.
Total stress relaxation depends on
the applied stress level. Furthermore,
it is increased to some extent by cold
deformation.
100
Residual Stress (%)
90
80
70
60
50
40
Temper
R620, Y550, R650, R690
Temper
R760, TR02
7.0
8.0
9.0
10.0
Larson-Miller parameter P
11.0
Fatigue Strength
The fatigue strength is defined as the maximum bending stress amplitude which a material withstands for 107 load cycles
under symmetrical alternate load without breaking. It is dependent on the temper tested and is about 1/3 of the tensile
strength Rm.
· Standard coils with outside
diameters up to 1400 mm
· Traverse-wound coils with drum weights up to 1.5 t
· Multicoil up to 5 t
Wieland-Werke AG
Dimensions Available
· Hot-dip tinned strip
· Contour-milled strip
· Sheet
· Strip and sheet with protective
coating
www.wieland.com
Graf-Arco-Str. 36, 89079 Ulm, Germany, Phone +49 731 944 2030, Fax +49 731 944 4257, info@wieland.de
This printed matter is not subject to revision. No claims can be derived from it unless there is evidence of intent or gross negligence.
The product characteristics are not guaranteed and do not replace our experts’ advice.
· Strip thickness from 0.10 mm,
thinner gauges on request
· Strip width from 3 mm,
however min. 10 x strip thickness
10/14 Bm (R+G)
Types and Formats Available