Page 430 - Analysis and Design of Machine Elements

Analysis and Design of Machine Elements
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Figure 14.16 Tensile elastic limit strength of spring materials. Source: Hindhede et al. 1983, figure 8-3,
p179. Reproduced with permission of John Wiley & Sons, Inc.

Table 14.3 Allowable stress of spring materials [1, 2, 7].

Stress types Materials
High carbon Stainless
Oil tempered steels steels Copper alloys

Static loads 0.55 b 0.50 b 0.45 b 0.40 b
3
Allowable shear (N < 10 )
stress for Finite fatigue life 0.45 0.42 0.36 0.35
compression 3 6 b b b b
springs [ ] (10 ≤ N ≤ 10 )
(MPa) Infinite 0.38 b 0.36 b 0.32 b 0.32 b
fatigue life
6
(N > 10 )
Static loads Multiply 80% of the above corresponding data
3
Allowable shear (N < 10 )
stress for Finite fatigue life
extension 3 6
springs [ ] (10 ≤ N ≤ 10 )
(MPa) Infinite
fatigue life
6
(N > 10 )
Static loads 0.80 b 0.78 b 0.75 b 0.75 b
3
Allowable (N < 10 )
bending stress Finite fatigue life 0.64 0.62 0.60 0.60
for torsion 3 6 b b b b
springs [ ] (10 ≤ N ≤ 10 )
b
(MPa) Infinite 0.55 b 0.54 b 0.50 b 0.50 b
fatigue life
6
(N > 10 )