Relations between fatigue strength and other mechanical properties of metallic materials

Abstract

The relations between fatigue strength and other mechanical properties especially the tensile strength of metallic materials are reviewed. After analyzing the numerous fatigue data available, the qualitative or quantitative relations between fatigue strength and hardness, strength (tensile strength and yield strength) and toughness (static toughness and impact toughness) are established. Among these relations, the general relation between fatigue strength σw and tensile strength σb, σw = σb(C − P ⋅ σb), where C and P are parameters, (hereafter, the general fatigue formula) can well predict the fatigue strength with increasing the tensile strength in a wide range for many materials such as conventional metallic materials, newly developed materials and engineering components. On the basis of the experimental results of many materials, the fatigue damage mechanism, especially for high‐strength steels, is proposed. It is suggested that the general fatigue formula can provide a new clue to predict the fatigue strength and design the materials by adjusting material parameters P and C adequately.

Fatigue strength dependence on the ultimate tensile strength and hardness in magnesium alloys

“…[22] and 5 MPa was chosen as step size. The tests were conducted in such a way that if the Table 1 Relationships between fatigue strength (r f ) and tensile properties (ultimate tensile strength r b and yield strength r 0.2 ) in different alloy systems [26][27][28][29][30][31][32][33][34][35][36][37][38][39].…”

“…Ferrous metals r f = (0.4-0.5)r b [26] r f = mr 0.2 + n AISI 4340 r f = 0.22r 0.2 + 335 [27] r f = (m-n Á r b ) Á r b…”

“…Since then, the liner relationships have been reported for cast steels and other alloys (such as copper, aluminum and titanium) between fatigue strength and tensile strengths (yield strength r 0.2 and/or ultimate tensile strength r b ) or hardness (abbrev. H, including Hv (Vickers hardness), H B (Brinell hardness), H RC (Rockwell hardness)) [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44], as shown in Tables 1 and 2. This paper aims to examine if there exists a linear relationship between fatigue strength and tensile strength or hardness. If there is, it will be much easier to estimate the fatigue strength from the tensile or hardness testing results without conducting costly and time-consuming fatigue testing.…”

A prediction method for fatigue life of large moving components as function of scale factor: A case of motor‐generator rotor

“…However, to pursue the accuracy or applicability of the method, there are too many parameters in those methods, which are inconvenient to use. In addition, predicting fatigue properties (eg, fatigue strength or fatigue limit) through a simple mechanical property such as static property (eg, tensile strength and hardness) is also an important research area . Since the S‐N curve is the basis of stress‐based method, fatigue testing blindly will consume plenty of time and expenses especially for HCF experiment .…”

“…In addition, predicting fatigue properties (eg, fatigue strength or fatigue limit) through a simple mechanical property such as static property (eg, tensile strength and hardness) is also an important research area. 1,23 Since the S-N curve is the basis of stress-based method, fatigue testing blindly will consume plenty of time and expenses especially for HCF experiment. 24 Meanwhile, the finite element method (FEM) has proven to be a very efficient tool for fatigue design and life prediction.…”