Ke Zhang

TL;DR: In this paper, the dendritic microstructure, crystal orientation and hot cracking behavior were studied by using optical microscopy, scanning electron microscopy (SEM) and electron backscatter diffraction (EBSD) techniques.

TL;DR: In this paper, the authors investigated the effect of grain boundary misorientation on susceptibility to liquation cracking in laser additive manufactured Inconel 718, and the results showed that the tendency of liquation film to crack increased with grain boundary angle, which was considered to be attributed to the higher stability of liquid at larger grain boundary during the last stage of solidification.

Abstract: A high-strength martensitic steel treated by a quenching–partitioning–tempering process is presented to examine the effect of retained austenite on ductility enhancement in martensitic steels. Results from X-ray diffraction line profile analysis (XLPA) indicate that the average dislocation density in martensite during uniform deformation is lower than before deformation, which effectively intensifies the deformation ability. The average dislocation density in retained austenite rapidly increases with increased strain and exceeds that in martensite. Based on the XLPA results, a new effect of austenite on the ductility enhancement is proposed: the austenite phase can continuously absorb ample dislocations from neighbouring martensite laths. This effect is indirectly verified by transmission electron microscopy.

TL;DR: In this paper, an in situ synthesized high volume fraction WC reinforced Ni-based composite coating was fabricated on a mild steel substrate by using a high power diode laser, and three kinds of single-layer coatings of different amounts of W+C powder and Ni60 powder were prepared.

TL;DR: In this paper, the effect of retained austenite on the ductility enhancement of bainitic steels was investigated by using X-ray diffraction (XRD) measurements of retained Austenite fraction in various deformation stages.