Literature Review on the Fatigue Properties of Materials Processed by Surface Mechanical Attrition Treatment (SMAT)

Abstract

As a promising surface treatment technique, the surface mechanical attrition treatment (SMAT) has been applied to enhance mechanical properties of various materials. Through multidirectional severe plastic deformation, SMAT is able to nanocrystallize the near surface region of materials. The nanostructured layer associated with high compressive residual stresses coupled with a work hardening layer can provide the treated materials with an improved fatigue resistance. The present work gives a comprehensive review on the fatigue strength of SMATed materials. First of all, a brief introduction is given on the basic elements of SMAT and surface modifications induced by this treatment. The fatigue strength of a large variety of SMATed materials with different loading conditions is reviewed, including low-cycle fatigue (LCF), high-cycle fatigue (HCF) and very-high-cycle fatigue (VHCF). Then, the mechanism of enhancement or reduction is explained through a detailed review on the effects of several factors, such as residual stress, surface quality and nanocrystalline grains. In addition, the combined effect of SMAT coupled with other processes is also reviewed. Trends and prospects of the current research are summarized at the end.

An Overview on Recent Works of Heterostructured Materials Fabricated by Surface Mechanical Attrition Treatment

“…12,17) In addition, mechanical twins can be promoted by other processing factors, such as low temperatures or high strain rates, which will be discussed more later. 12,99) The traditional gradient structure is generally surface grain size gradient or surface nano twin gradient. The reinforcement generated by them has been reported and summarized, which has made great progress so far.…”

“…For example, the effect of residual stress on cyclic fatigue resistance has been studied. 99) However, the intrinsic relationship between residual stress and tensile mechanical behavior of GS materials is unclear.…”

Surface Severe Plastic Deformation for Improved Mechanical/Corrosion Properties and Further Applications in the Bio-Medical and Hydrogen Sectors

“…Several review papers dealing with the fatigue behaviour of metals subjected to different types of SSPD treatments have been published recently. 89,90) Factors affecting the fatigue life of a component can be roughly divided into two main categories. First, the surface roughness or the presence of stress raisers, influence essentially the initiation stage of crack growth.…”

Mechanical Properties of Metallic Materials Processed by Surface Severe Plastic Deformation

“…Under the effect of SSPD, the hardness of the near surface region should be higher due to the generated work hardening and grain refinement. 48,145,146) It is generally considered that work hardening induced by SSPD is beneficial for improving mechanical strength of materials due to the increased yield strength. However, if the SSPD processed materials undergo cyclic loading and exhibit Bauschinger effect, it would be necessary to distinguish isotropic hardening and kinematic hardening.…”