The effect of aging temperature on erosion corrosion (E-C) behavior of 17-4PH stainless steels in dilute sulphuric acid slurry containing solid particles was studied by using self-made rotating E-C apparatus. The ef...The effect of aging temperature on erosion corrosion (E-C) behavior of 17-4PH stainless steels in dilute sulphuric acid slurry containing solid particles was studied by using self-made rotating E-C apparatus. The effect of impact velocity on EC behavior of 17 4PH steels at different aging temperatures was analyzed. Surface micrographs of the specimens after E C test were observed by using scanning electron microscope (SEM). The results showed that under the condition of the same solution heat treatment, when aging temperature ranged from 400 ℃ to 610℃, the hardness reached the highest value near the temperature 460℃. The characteristics of E-C for 17-4PH stainless steels at different aging temperatures were as follows: pure erosion (wear) was dominant, corrosion was subordinate and at the same time corrosion promoted erosion. The effect of aging temperature on E-C rate of 17-4PH steels was not significant at low impact velocity, but it was found that E-C resistance of 17-4PH steels aged near 460℃ was the most excellent due to the best precipitation strengthening effect of fine and dispersed e-Cu phase. With a prerequisite of appropriate corrosion resistance, the precipitation hardening could significantly improve the E-C resistance of the materials.展开更多
The effect of aging temperature on stress corrosion crocking of 17-4 precipitation-hardened(PH)stainless steel in simulated stimulant oil well environment was studied by the method B-NACE standard bent-beam test.It is...The effect of aging temperature on stress corrosion crocking of 17-4 precipitation-hardened(PH)stainless steel in simulated stimulant oil well environment was studied by the method B-NACE standard bent-beam test.It is found that when aging temperature ranges from 480 to 610℃,the sensitivity of hydrogen embrittlement decreases significantly.展开更多
The stress corrosion cracking( SCC) behavior of PH13-8Mo precipitation hardening stainless steel( PHSS) in neutral NaCl solutions was investigated through slow-strain-rate tensile( SSRT) test at various applied ...The stress corrosion cracking( SCC) behavior of PH13-8Mo precipitation hardening stainless steel( PHSS) in neutral NaCl solutions was investigated through slow-strain-rate tensile( SSRT) test at various applied potentials. Fracture morphology,elongation ratio,and percentage reduction of area were measured to evaluate the SCC susceptibility. A critical concentration of 1. 0 mol / L neutral NaCl existed for SCC of PH13-8Mo steel. Significant SCC emerged when the applied potential was more negative than -0. 15 VSCE,and the SCC behavior was controlled by an anodic dissolution( AD) process.When the applied potential was lower than -0. 55 VSCE,an obvious hydrogen-fracture morphology was observed,which indicated that the SCC behavior was controlled by hydrogen-induced cracking( HIC).Between -0. 15 and -0. 35 VSCE,the applied potential exceeded the equilibrium hydrogen evolution potential in neutral NaCl solutions and the crack tips were of electrochemical origin in the anodic region; thus,the SCC process was dominated by the AD mechanism.展开更多
文摘The effect of aging temperature on erosion corrosion (E-C) behavior of 17-4PH stainless steels in dilute sulphuric acid slurry containing solid particles was studied by using self-made rotating E-C apparatus. The effect of impact velocity on EC behavior of 17 4PH steels at different aging temperatures was analyzed. Surface micrographs of the specimens after E C test were observed by using scanning electron microscope (SEM). The results showed that under the condition of the same solution heat treatment, when aging temperature ranged from 400 ℃ to 610℃, the hardness reached the highest value near the temperature 460℃. The characteristics of E-C for 17-4PH stainless steels at different aging temperatures were as follows: pure erosion (wear) was dominant, corrosion was subordinate and at the same time corrosion promoted erosion. The effect of aging temperature on E-C rate of 17-4PH steels was not significant at low impact velocity, but it was found that E-C resistance of 17-4PH steels aged near 460℃ was the most excellent due to the best precipitation strengthening effect of fine and dispersed e-Cu phase. With a prerequisite of appropriate corrosion resistance, the precipitation hardening could significantly improve the E-C resistance of the materials.
文摘The effect of aging temperature on stress corrosion crocking of 17-4 precipitation-hardened(PH)stainless steel in simulated stimulant oil well environment was studied by the method B-NACE standard bent-beam test.It is found that when aging temperature ranges from 480 to 610℃,the sensitivity of hydrogen embrittlement decreases significantly.
基金supported by the National Natural Science Foundation of China(No.51171023)the Fundamental Research Funds for the Central Universities(No.FRF-TP-14-011C1)+1 种基金National Basic Research Program of China(973 Program )(No.2014CB643300 )the Beijing Municipal Commission of Education
文摘The stress corrosion cracking( SCC) behavior of PH13-8Mo precipitation hardening stainless steel( PHSS) in neutral NaCl solutions was investigated through slow-strain-rate tensile( SSRT) test at various applied potentials. Fracture morphology,elongation ratio,and percentage reduction of area were measured to evaluate the SCC susceptibility. A critical concentration of 1. 0 mol / L neutral NaCl existed for SCC of PH13-8Mo steel. Significant SCC emerged when the applied potential was more negative than -0. 15 VSCE,and the SCC behavior was controlled by an anodic dissolution( AD) process.When the applied potential was lower than -0. 55 VSCE,an obvious hydrogen-fracture morphology was observed,which indicated that the SCC behavior was controlled by hydrogen-induced cracking( HIC).Between -0. 15 and -0. 35 VSCE,the applied potential exceeded the equilibrium hydrogen evolution potential in neutral NaCl solutions and the crack tips were of electrochemical origin in the anodic region; thus,the SCC process was dominated by the AD mechanism.