Evolution Behaviors and Mechanisms of Internal Crack Healing in Steels at Elevated Temperatures
- PDF / 6,025,430 Bytes
- 12 Pages / 593.972 x 792 pts Page_size
- 58 Downloads / 215 Views
ION
CRACKS in metallic materials are inevitable during the processing, manufacturing, and using of workpieces.[1] Cracking is one of the most common failure modes for materials.[2] Crack healing is of great value to initial manufacturing as well as remanufacturing engineering. Healing cracks in metallic materials can reduce rejection rates and prolong service life, protect the environment, and save energy.[3] Therefore, in the last 2 decades, crack healing in metallic materials has attracted extensive attention from researchers. In existing studies, researchers investigated crack healing behaviors and mechanisms in metallic materials with different methods from various aspects and obtained plenty of valuable results. For instance, Han et al.[4] found the crack healing phenomenon in 20MnMo steel earlier and reported that crack healing mainly depended on atomic diffusion and migration.
RUI-SHAN XIN, SHUAI REN, HUI-LONG AN, JI-TAN YAO, JIN PAN, and LI SUN are with the HBIS Group Technology Research Institute, Shijiazhuang 050023, P.R. China. Contact email: [email protected] JU KANG is with the School of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, P.R. China. QING-XIAN MA is with the Department of Mechanical Engineering, Tsinghua University, Beijing 100084, P.R. China. Contact e-mail: [email protected] Manuscript submitted February 13, 2018.
METALLURGICAL AND MATERIALS TRANSACTIONS A
Zhong et al.[5] also investigated the crack healing in 20MnMo steel but considered that it was mainly controlled by recrystallization and grain growth. Zhang et al.[6,7] analyzed the morphological healing evolution of fatigue microcracks in iron at elevated temperatures and considered that penny-shaped microcracks evolved into an isolated spherical void via surface diffusion. Zhou et al.[8] reported that cracks in a steel could be healed using the electropulsing technique, and the possible reasons for crack healing were the generation of plasma and the motion of effective atoms toward crack. Yu et al.[9] studied crack healing in SUS 304 stainless steel and found that the process of rapid melting and solidification had occurred in healing areas with the formation of columnar crystals and fine recrystallization zone. Gao et al.[10] investigated crack healing in a-Fe during heating from in-situ transmission electron microscopy (TEM) observation and pointed out that crack healing is due to self-diffusion of a-Fe atoms. Song et al.[11] also carried out in-situ TEM observation on submicron-scale void healing in an Al-Mg-Er alloy and proposed that lattice diffusion dominated the entire healing process. Gao et al.[12] analyzed internal crack healing mechanisms of plain carbon steel under rolling deformation and found that crack healing was controlled by atomic diffusion and also by nucleation and growth of ferrite grains on the crack surface. Song and Wang[13] found the occurrence of local recrystallization accompanied with damage healing. Void and crack healing in polycrystalline metals
under u
Data Loading...
