378
T. A. Musalli et al.
helical spring fatigue analysis. Del Llano-Vizcaya et al. [2] have compared experimental fatigue life with multiaxial fatigue criteria prediction method based on shear
deformation. The finite element code ANSYS was used for stress analysis, and a
multi-axis fatigue study was carried out using the fatigue software nCode. The results
emphasize that the fatigue life of the helical spring component could be adequately
predicted by the Fatemi-Socié critical surface method. Based on the strain life finite
element method, Kamal and Rahman [3] were investigated the fatigue behavior of
shock absorber springs used in automotive suspension systems made of SAE 9254
material. Mulla et al. [4] were conducted a fatigue analysis on the helical compression
springs used in three wheeler’s auto-rickshaw. The FEA results emphasize that classical models were less accurate when compared with these spring geometries. When
compared to the value calculated using a simple analytical model, the maximum
shear stress error obtained was limited to 1.5–4%. In this work, the applicability of a
multi-axial non-proportional approach on the compression spring analysis was investigated. Stress and strain life analyses were tested to determine equivalent Von-Mises
and maximum shear stresses. The estimated lifetime was compared with theoretical
calculations to evaluate the various numerical analysis criteria. The multi-axial nonproportional fatigue analysis is yielded minimal error between the numerical and
theoretical analysis.
2 Spring Geometry, Loading Condition and Material
2.1 Spring Geometry and Applied Loads
In this study, a standard helical compression spring DIN 2098-1 [5] without heat
treatment was considered. It is made of chrome-silicon AISI 9254 [6] with both ends
squared and ground. This spring is to be assembled with a preload of a minimum of
F min = 60 N and will operate with a maximum load of F max = 500 N during use.
The nomenclature of the spring is listed in Table 1 and the spring geometry is shown
in Fig. 1.
2.2 Material Properties
AISI 9254 chrome-silicon is an alloy to withstand high-loading of springs, which are
subjected to shock loads and require a long service life. It has a great hardness and is
able to use it in a high-temperature condition up to 250 °C [6]. Its fatigue Stress-life
and Strain-life characteristics were obtained from the nCode (FEA) software material
library [7]. The mechanical property of the considered materials is given in Table 2.
In order to perform strain-life fatigue analysis approach, various parameters have
to be considered for Chrome-silicon AISI 9254 which are given in Table 3.
T. A. Musalli et al.
helical spring fatigue analysis. Del Llano-Vizcaya et al. [2] have compared experimental fatigue life with multiaxial fatigue criteria prediction method based on shear
deformation. The finite element code ANSYS was used for stress analysis, and a
multi-axis fatigue study was carried out using the fatigue software nCode. The results
emphasize that the fatigue life of the helical spring component could be adequately
predicted by the Fatemi-Socié critical surface method. Based on the strain life finite
element method, Kamal and Rahman [3] were investigated the fatigue behavior of
shock absorber springs used in automotive suspension systems made of SAE 9254
material. Mulla et al. [4] were conducted a fatigue analysis on the helical compression
springs used in three wheeler’s auto-rickshaw. The FEA results emphasize that classical models were less accurate when compared with these spring geometries. When
compared to the value calculated using a simple analytical model, the maximum
shear stress error obtained was limited to 1.5–4%. In this work, the applicability of a
multi-axial non-proportional approach on the compression spring analysis was investigated. Stress and strain life analyses were tested to determine equivalent Von-Mises
and maximum shear stresses. The estimated lifetime was compared with theoretical
calculations to evaluate the various numerical analysis criteria. The multi-axial nonproportional fatigue analysis is yielded minimal error between the numerical and
theoretical analysis.
2 Spring Geometry, Loading Condition and Material
2.1 Spring Geometry and Applied Loads
In this study, a standard helical compression spring DIN 2098-1 [5] without heat
treatment was considered. It is made of chrome-silicon AISI 9254 [6] with both ends
squared and ground. This spring is to be assembled with a preload of a minimum of
F min = 60 N and will operate with a maximum load of F max = 500 N during use.
The nomenclature of the spring is listed in Table 1 and the spring geometry is shown
in Fig. 1.
2.2 Material Properties
AISI 9254 chrome-silicon is an alloy to withstand high-loading of springs, which are
subjected to shock loads and require a long service life. It has a great hardness and is
able to use it in a high-temperature condition up to 250 °C [6]. Its fatigue Stress-life
and Strain-life characteristics were obtained from the nCode (FEA) software material
library [7]. The mechanical property of the considered materials is given in Table 2.
In order to perform strain-life fatigue analysis approach, various parameters have
to be considered for Chrome-silicon AISI 9254 which are given in Table 3.