Dimensional consistency achieved in high-performance synchronizing hubs


  • P. García Quality Manager PMG Asturias Powder Metal S.A.U.
  • M. Campos Materials Science and Engineering Department, Universidad Carlos III de Madrid
  • J. M. Torralba Materials Science and Engineering Department, Universidad Carlos III de Madrid - IMDEA Materials Institute




Double pressing and sintering, Dimensional control, High performance parts


The tolerances of parts produced for the automotive industry are so tight that any small process variation may mean that the product does not fulfill them. As dimensional tolerances decrease, the material properties of parts are expected to be improved. Depending on the dimensional and material requirements of a part, different production routes are available to find robust processes, minimizing cost and maximizing process capability. Dimensional tolerances have been reduced in recent years, and as a result, the double pressing-double sintering production via (“2P2S”) has again become an accurate way to meet these increasingly narrow tolerances. In this paper, it is shown that the process parameters of the first sintering have great influence on the following production steps and the dimensions of the final parts. The roles of factors other than density and the second sintering process in defining the final dimensions of product are probed. All trials were done in a production line that produces synchronizer hubs for manual transmissions, allowing the maintenance of stable conditions and control of those parameters that are relevant for the product and process.


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How to Cite

García, P., Campos, M., & Torralba, J. M. (2013). Dimensional consistency achieved in high-performance synchronizing hubs. Revista De Metalurgia, 49(1), 55–64. https://doi.org/10.3989/revmetalm.1218




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