Influence of dead metal zone on dislocation strengthening effect during micro-progressive forming

  • J. Q. Ran
  • L. Xu
  • J. L. Wang
  • T. Xu
  • F. GongEmail author


Micro-scale plastic deformation (microforming) is a promising manufacturing technology in modern industries. To put microformed parts in a more competitive position compared with micro-products made by other micro-manufacturing methods (such as micromachining and 3D printing), micro-progressive forming must be fully studied for the mass production of micro-parts to obtain good grain texture and decrease product costs. Simultaneously, the undiscovered dislocation strengthening effect of micro-scale progressive forming should be investigated. Using micro-universal joint progressive forming as a case study, the influence of the dead metal zone–induced strengthening effect on ductile fracture in micro-progressive forming is discussed. Based on the results of upsetting experiment and finite element simulation, it was found that the specimen produced via metal foil forward-extrusion-blanking process eliminated the ductile fracture when applying the same experiment condition to the specimen produced by micromachining. Based on the micro-indentation and X-ray diffraction results, a dead metal zone–induced dislocation strengthening model was established, and the mechanism for the strengthening effect during micro-progressive forming was revealed. This research thus provides an in-depth understanding of the micro-scale progressive forming process and takes an important step in the field of ductile fracture in multi-stage plastic deformation.


Micro-progressive forming Strengthening effect Dead metal zone Multi-stage plastic deformation 


Funding information

The work described in this paper was supported by grants from the National Natural Science Foundation of China (Grant No. 51705333), the key laboratory of Guangdong Province and the Natural Science Foundation of Guangdong Province (Grant No. 2017A030310352), the Natural Science Foundation of ShenZhen University (Grant No. 2016039), the open project of the key laboratory of Guangdong Province (PEM201605), and the Shenzhen Science and Technology Program (Grant Nos. JCYJ20160520175255386 and JCYJ20170818104529523).


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Copyright information

© Springer-Verlag London Ltd., part of Springer Nature 2019

Authors and Affiliations

  • J. Q. Ran
    • 1
  • L. Xu
    • 1
  • J. L. Wang
    • 2
    • 3
  • T. Xu
    • 1
  • F. Gong
    • 1
    Email author
  1. 1.College of Mechatronics and Control EngineeringShenzhen UniversityShenzhenChina
  2. 2.Shenzhen Research Institute of Shandong UniversityShenzhenChina
  3. 3.School of Mechanical EngineeringShandong UniversityJinanChina

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