Imperial College London
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DrZhutaoShao

Faculty of Engineering, Department of Mechanical Engineering

Research Associate
 
 
 
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Contact

 

z.shao12

 
 
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Location

 

City and Guilds BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Zhou:2020:10.1016/j.ijmachtools.2020.103647,
author = {Zhou, X and Shao, Z and Zhang, C and Sun, F and Zhou, W and Hua, L and Jiang, J and Wang, L},
doi = {10.1016/j.ijmachtools.2020.103647},
journal = {International Journal of Machine Tools and Manufacture},
title = {The study of central cracking mechanism and criterion in cross wedge rolling},
url = {http://dx.doi.org/10.1016/j.ijmachtools.2020.103647},
volume = {159},
year = {2020}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Cross wedge rolling (CWR) is an innovative metal forming process to manufacture axisymmetric stepped shafts used in the transport industry. Central cracking, also called the Mannesmann Effect, consistently occurs in the central region of the CWR workpiece. This results in reduced product quality and increased costs due to rejected and failed parts. However, the understanding of central cracking mechanism and criterion is limited due to the complex stress states in CWR and the experimental limitations. A large number of CWR tests and different die geometries are required in the identification of the potential mechanistic factors such as the axial tensile stress, secondary tensile stress, shear stress and cyclic loading. Also, there is as yet no efficient method of determining the material constants associated with the central cracking fracture criteria. These problems are addressed in the present study. A physical model was built to reproduce the industrial CWR process. A newly designed model material (plasticine/flour composite) was used to mimic the material flows and internal fracture behaviours found in commercial CWR workpieces. This allowed a variety of die shapes to be rapidly and cost-effectively 3D printed, thereby enabling specific stress states to be achieved within the workpiece. Via experimental observations and the corresponding finite element modelling under different die geometries, the maximum shear stress was identified as the dominant factor for central cracking. The fracture criterion involving the maximum shear stress was quantitatively verified to be accurate and robust in predicting central cracking moments and locations. A novel approach using simplified die geometries to determine the associated material constants was proposed and validated. The high accuracy and cost/time efficiency of this new approach will be a significant benefit to fundamental research and also in industrial applications.
AU  - Zhou,X
AU  - Shao,Z
AU  - Zhang,C
AU  - Sun,F
AU  - Zhou,W
AU  - Hua,L
AU  - Jiang,J
AU  - Wang,L
DO  - 10.1016/j.ijmachtools.2020.103647
PY  - 2020///
SN  - 0890-6955
TI  - The study of central cracking mechanism and criterion in cross wedge rolling
T2  - International Journal of Machine Tools and Manufacture
UR  - http://dx.doi.org/10.1016/j.ijmachtools.2020.103647
UR  - http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000596770300004&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=1ba7043ffcc86c417c072aa74d649202
UR  - https://www.sciencedirect.com/science/article/pii/S0890695520306635?via%3Dihub
UR  - http://hdl.handle.net/10044/1/85980
VL  - 159
ER  -
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