Declined Fatigue Crack Propagation Rate of a High‐Strength Steel by Electropulsing Treatment

Abstract

The fatigue crack propagation behavior is a key issue for the service of engineering materials. The effect of electropulsing treatment (EPT) on the growth of fatigue crack in a high‐strength steel (AISI 4340 steel) is investigated. It is shown that the crack propagation rate could be significantly declined via high‐density EPT. The crack features of fracture surface are examined using laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM). The crack deviation, local crack‐healing and bridging phenomenon are proposed to be beneficial to lower the crack propagation rate, which should be brought out by the current detour, selective Joule heating, compressive stress, and electrical breakdown phenomenon. All these EPT effects exhibit significant contributions to the improvement of fatigue properties in the widely used high‐strength steel.

The fatigue crack behavior of 7N01-T6 aluminum alloy in different particle environments

“…Recently, Ben et al found that [45] the FCGRs of a high-strength steel declined slightly after electro-pulsing treatment because of formation of many molten beads in Fig. 13 a SEM image and (b) schematic diagram of particle distribution on the fracture surfaces fatigue loaded in air; c SEM image and (d) schematic diagram of particle distribution on the fracture surfaces in a graphite-particle environment; e SEM image and (f) schematic diagram of particle distribution on the fracture surfaces in a CaO-particle environment; g SEM image and (h) schematic diagram of particle distribution on the fracture surfaces in an Al 2 O 3 -particle environment; i SEM image and (j) schematic diagram of particle distribution on the fracture surfaces in an the fatigue crack.…”

Voids healing and carbide refinement of cold rolled M50 bearing steel by electropulsing treatment

“…However, when kinetic diffusion of carbon atoms is accelerated by the pulsed electric, the localized carbide dissolution would occur within a short time. Meanwhile, it should be noted that the detour effect 30 of electric current results in a higher joule heating adjacent to voids and the tip region of carbide than the overall estimated temperature (532 °C), which will lead the local temperature of carbides to be close to the thermodynamic dissolution temperature. Since the thermodynamic dissolution temperature of Cr-rich carbides is lowest 23 , the partial dissolution and refinement could be easier to achieve.…”

A State‐of‐Art Review on Prediction Model for Fatigue Performance of Welded Joints via Data‐Driven Method

“…After crack initiation, the fatigue crack growth rate (FCGR) can describe the residual fatigue life of materials. [167,168] Moreover, Figure 15. Comprehensive evaluation of the IFs of fatigue damage.…”

“…After crack initiation, the fatigue crack growth rate (FCGR) can describe the residual fatigue life of materials. [ 167,168 ] Moreover, the evaluation of residual fatigue life can be supported by the prediction of fatigue crack characteristics. Currently, the mechanism explanation of FCGR prediction is still a difficult topic for data‐driven methods.…”