Microstructure Evolution and Microhardness of Ultrafine-grained High Carbon Steel during Multiple Laser Shock Processing

• Published in: Journal of iron and steel research, international Vol. 22; no. 1; pp. 55 - 59
• Main Authors: XIONG, Yi, HE, Tian-tian, REN, Feng-zhang, LI, Peng-yan, CHEN, Lu-fei, VOLINSKY, Alex A.
• Format: Journal Article
• Language: English
• Published: Singapore Elsevier Ltd 2015; Springer Singapore
• Subjects: Applied and Technical Physics; Cementite; Engineering; High carbon steels; impact times; Iron and steel industry; Laser shock processing; Machines; Manufacturing; Material; Materials Engineering; Materials Science; Metallic Materials; Microhardness; Microstructure; Physical Chemistry; Processes; Scanning electron microscopy; Spheroidizing; ultrafine-grained high carbon steel; 扫描电子显微镜; 显微硬度; 激光冲击处理; 组织演变; 表面微观结构; 超细晶粒; 透射电子显微镜; 高碳钢; laser shock processing; microhardness; microstructure; ultrafine-grained high carbon steel; impact times
• ISSN: 1006-706X; 2210-3988
• DOI: 10.1016/S1006-706X(15)60009-7

Surface microstructure and microhardness of （ferrite＋ cementite） microduplex structure of the ultrafine- grained high carbon steel after laser shock processing （LSP） with different impact times were investigated by means of scanning electron microscopy （SEM）, transmission electron microscopy （TEM）, X-ray diffraction （XRD） and microhardness measurements. Equiaxed ferrite grains were refined from 400 to 150 nm, and the cementite lamellae were fully spheroidized, with a decrease of the particle diameter from 150 to 100 nm as the impact times increased. The cementite dissolution was enhanced significantly. Correspondingly, the lattice parameter of α-Fe and microhard- hess increased with the impact times.