Experimental study of the fretting wear behavior of Inconel 690 alloy under alternating load conditions

Abstract

This study investigated the fretting wear behavior of the nuclear power material Inconel 690 alloy. An improved PLINT high-temperature fretting tester was used on an Inconel 690 tube against a 1Cr13 cylinder at different temperatures (25 C and 300 C) under alternating load conditions. The fretting-wear mechanism and the kinetic characteristic of Inconel 690 alloy were analyzed. Results showed that the fretting running behavior was closely related to the normal excitation frequency. In parallelogram shaped F t-D curves, the friction fluctuates periodically, and accordingly the fretting was running in the slip regime. The steady-state friction force at room temperature in air was higher than that at 300 C. Moreover, the damage behavior of the fretting for Inconel 690 alloy strongly depended on the normal load, displacement amplitude, temperature, and excitation frequency in atmospheric environment. A superposition effect of fretting wear behavior was discovered because of the combined effect of alternating normal and tangential forces; thus, delamination became more significant. Abrasive wear and delamination were the major mechanisms in Inconel 690 alloy at room temperature in ambient air. The dominant mechanisms at 300 C were the abrasive wear, oxidation wear, and delamination.

Effects of Temperature on the Fretting Wear Behavior of 2.25Cr-1Mo Tubes against Gr5C12 Rods

“…The maximum average COF in the stable stage is 0.500 at 80 °C, and the minimum COF is 0.451 in the stable stage at 450 °C ( Figure 2 d). The COF also increases with the increase in load and amplitude [ 16 , 19 ].…”

“…The fretting maps of the three groups of tests after 10 4 cycles are shown in Figure 3 . In general, temperature exerts some influence on the fretting model, but greater influence comes from the normal load and sliding displacement [ 16 , 32 ]. At 20 N, the fretting map is linear at room temperature or a high temperature, indicating that the fretting model is a partial slip condition.…”

“…In the second step, the upper sample (9) was fixed on the upper fixture (10), and the upper fixture (10) and heat insulation plate (11) were fixed onto the equipment together. In the third step, the temperature control box (16) was used to control the heating rod (7) for heat generation until the temperature sensor (5) returned a temperature that reached a preset value. In the fourth step, the spinner handle (15) was used to drop the horizontal position of the upper sample (9) until it simply made contact with the lower sample (8).…”

“…The 690 alloy was widely used in heat transfer tubes in the second generation of pressurized water reactors due to its excellent intergranular corrosion and intergranular stress corrosion cracking properties [ 7 ]. In recent years, fretting wear research on Inconel 690 alloys has covered contact forms [ 8 , 9 ], environment and temperatures [ 10 , 11 , 12 ], loads, and displacements [ 13 , 14 , 15 , 16 ]. In addition, a number of studies have focused on the effects of grain size and hardness [ 17 ], carbide size, and spacing [ 18 ] on the fretting wear properties of Inconel 690.…”

Ti-6Al-4V fretting wear and a quantitative indicator for fretting regime evaluation

“…However, under other test conditions (fretting run in gross slip regime and the mixed regime), Fx/Fz rose at the initial stage and then tended to be stable. 33 When the fretting run in gross slip regime, the contacting surfaces between the two samples experienced high frequency rubbing. As a result, the wear of the upper sample (ball) was inevitable, and the ball wore off a spherical crown.…”