Decrease in Hydrogen Embrittlement Susceptibility of 10B21 Screws by Bake Aging

Abstract

Abstract:The effects of baking on the mechanical properties and fracture characteristics of low-carbon boron (10B21) steel screws were investigated. Fracture torque tests and hydrogen content analysis were performed on baked screws to evaluate hydrogen embrittlement (HE) susceptibility. The diffusible hydrogen content within 10B21 steel dominated the fracture behavior of the screws. The fracture torque of 10B21 screws baked for a long duration was affected by released hydrogen. Secondary ion mass spectroscopy (SIMS) result showed that hydrogen content decreased with increasing baking duration, and thus the HE susceptibility of 10B21 screws improved. Diffusible hydrogen promoted crack propagation in high-stress region. The HE of 10B21 screws can be prevented by long-duration baking.

Effects of Tempered Microstructure and Hydrogen Concentration on Hydrogen-Induced Embrittlement Susceptibility of 10B21 Screws at Low Temperature

“…Compared with unbaked screws, the proportion of hydrogen content in the screws respectively decreased by 74% and 82% after baking for 8 and 16 h, respectively, and thus affected HAE susceptibility of screw. 10) In order to prevent HIE, the baking duration should exceed 8 h. The effect of baking duration on the ultimate torque strength determined using Weibull analysis 18) is plotted in Fig. 5.…”

“…9) Martensite is most susceptible to hydrogen damage, whereas temperted martenstie is least susceptible. 10) A threaded fastener specimen can essentially be examined with several notches that act as stress risers under hydrogen embrittlement (HE) test, which usually fractures at the thread root radius, shank, or the head-to-shank fillet. Notches sensitivity produced by threads on fasteners has an effect on the maximum load and affected by mechanical properties of the 10B21 screw.…”

Comparison of the Tribological Properties of the Thermal Diffusion Zinc Coating to the Classic and Heat Treated Hot-Dip Zinc Coatings

“…According to Kania [ 14 ], the corrosion resistance of electro-galvanized bolts decreases quickly due to the small coating thickness. Moreover, the application of this method may result in contamination of the natural environment and potential hydrogen embrittlement of the steel [ 18 , 19 , 20 ]. Although lamella zinc technology increases its market share, especially in the area of fasteners, i.e.…”

Study of correlation between the steels susceptibility to hydrogen embrittlement and hydrogen thermal desorption spectroscopy using artificial neural network

“…The effect of hydrogen-assisted damage can be significantly decreased by heat treatment at some stages of the steel processing causing the reduction of the total hydrogen concentration in the solid solution [14,16,17]. Worth to note is the diffusivity of the hydrogen in steels typically increases with tempering due to recovery and recrystallization resulting in a reduction of the defects density affecting the hydrogen detrapping and diffusion [18,19].…”